Open-access and free articles in Journal of Synchrotron Radiation
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Synchrotron radiation research is rapidly expanding with many new sources of radiation being created globally. Synchrotron radiation plays a leading role in pure science and in emerging technologies. The Journal of Synchrotron Radiation provides comprehensive coverage of the entire field of synchrotron radiation and free-electron laser research including instrumentation, theory, computing and scientific applications in areas such as biology, nanoscience and materials science. Rapid publication ensures an up-to-date information resource for scientists and engineers in the field.en-gbCopyright (c) 2024 International Union of CrystallographyInternational Union of CrystallographyInternational Union of CrystallographytextSynchrotron radiation research is rapidly expanding with many new sources of radiation being created globally. Synchrotron radiation plays a leading role in pure science and in emerging technologies. The Journal of Synchrotron Radiation provides comprehensive coverage of the entire field of synchrotron radiation and free-electron laser research including instrumentation, theory, computing and scientific applications in areas such as biology, nanoscience and materials science. Rapid publication ensures an up-to-date information resource for scientists and engineers in the field.https://journals.iucr.orgtext/htmlOpen-access and free articles in Journal of Synchrotron Radiationurn:issn:0909-0495yearly2002-01-01T00:00+00:006urn:issn:0909-0495Journal of Synchrotron RadiationCopyright (c) 2024 International Union of Crystallographymed@iucr.orgOpen-access and free articles in Journal of Synchrotron Radiationhttp://journals.iucr.org/logos/rss10s.gif
https://journals.iucr.org/s/journalhomepage.html
Still imageEfficient end-to-end simulation of time-dependent coherent X-ray scattering experiments
http://scripts.iucr.org/cgi-bin/paper?ok5105
Physical optics simulations for beamlines and experiments allow users to test experiment feasibility and optimize beamline settings ahead of beam time in order to optimize valuable beam time at synchrotron light sources like NSLS-II. Further, such simulations also help to develop and test experimental data processing methods and software in advance. The Synchrotron Radiation Workshop (SRW) software package supports such complex simulations. We demonstrate how recent developments in SRW significantly improve the efficiency of physical optics simulations, such as end-to-end simulations of time-dependent X-ray photon correlation spectroscopy experiments with partially coherent undulator radiation (UR). The molecular dynamics simulation code LAMMPS was chosen to model the sample: a solution of silica nanoparticles in water at room temperature. Real-space distributions of nanoparticles produced by LAMMPS were imported into SRW and used to simulate scattering patterns of partially coherent hard X-ray UR from such a sample at the detector. The partially coherent UR illuminating the sample can be represented by a set of orthogonal coherent modes obtained by simulation of emission and propagation of this radiation through the coherent hard X-ray (CHX) scattering beamline followed by a coherent-mode decomposition. GPU acceleration is added for several key functions of SRW used in propagation from sample to detector, further improving the speed of the calculations. The accuracy of this simulation is benchmarked by comparison with experimental data.textPhysical optics simulations for beamlines and experiments allow users to test experiment feasibility and optimize beamline settings ahead of beam time in order to optimize valuable beam time at synchrotron light sources like NSLS-II. Further, such simulations also help to develop and test experimental data processing methods and software in advance. The Synchrotron Radiation Workshop (SRW) software package supports such complex simulations. We demonstrate how recent developments in SRW significantly improve the efficiency of physical optics simulations, such as end-to-end simulations of time-dependent X-ray photon correlation spectroscopy experiments with partially coherent undulator radiation (UR). The molecular dynamics simulation code LAMMPS was chosen to model the sample: a solution of silica nanoparticles in water at room temperature. Real-space distributions of nanoparticles produced by LAMMPS were imported into SRW and used to simulate scattering patterns of partially coherent hard X-ray UR from such a sample at the detector. The partially coherent UR illuminating the sample can be represented by a set of orthogonal coherent modes obtained by simulation of emission and propagation of this radiation through the coherent hard X-ray (CHX) scattering beamline followed by a coherent-mode decomposition. GPU acceleration is added for several key functions of SRW used in propagation from sample to detector, further improving the speed of the calculations. The accuracy of this simulation is benchmarked by comparison with experimental data.urn:issn:1600-5775text/htmlEnd-to-end simulation of time-dependent partially coherent X-ray scattering experiments is demonstrated with the SRW code. A coherent-mode decomposition and GPU acceleration recently implemented in the code make such simulations feasible and efficient for a typical XPCS experiment at a storage ring light source. This enables more detailed tests and optimization of experimental configurations and data processing prior to beam time as well as understanding experimental data.2024-03-22SYNCHROTRON RADIATION WORKSHOP; X-RAY PHOTON CORRELATION SPECTROSCOPY; COHERENT-MODE DECOMPOSITION; GPU ACCELERATIONEfficient end-to-end simulation of time-dependent coherent X-ray scattering experimentsInternational Union of CrystallographyGoel, H.Chubar, O.Li, R.Wiegart, L.Rakitin, M.Fluerasu, A.doi:10.1107/S1600577524001267enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752024-03-22May 2024Journal of Synchrotron Radiation311600-57753https://creativecommons.org/licenses/by/4.0/research papersDevelopment of the multiplex imaging chamber at PAL-XFEL
http://scripts.iucr.org/cgi-bin/paper?ay5626
Various X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens.textVarious X-ray techniques are employed to investigate specimens in diverse fields. Generally, scattering and absorption/emission processes occur due to the interaction of X-rays with matter. The output signals from these processes contain structural information and the electronic structure of specimens, respectively. The combination of complementary X-ray techniques improves the understanding of complex systems holistically. In this context, we introduce a multiplex imaging instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to investigate morphological information with nanoscale resolution, crystal arrangement at the atomic scale and the electronic structure of specimens.urn:issn:1600-5775text/htmlA new instrument that can collect small-/wide-angle X-ray diffraction and X-ray emission spectra simultaneously to probe the physical and chemical structures of specimens is introduced.2024-03-22COHERENT DIFFRACTION IMAGING; WIDE-ANGLE X-RAY DIFFRACTION; X-RAY EMISSION SPECTROSCOPY; XFELS; ULTRAFAST DYNAMICSDevelopment of the multiplex imaging chamber at PAL-XFELInternational Union of CrystallographyHwang, J.Kim, S.Lee, S.Y.Park, E.Shin, J.Lee, J.H.Kim, M.-Kim, S.Park, S.-Y.Jang, D.Eom, I.Kim, S.Song, C.Kim, K.S.Nam, D.doi:10.1107/S1600577524001218enhttps://creativecommons.org/licenses/by/4.0/May 202431Journal of Synchrotron Radiation1600-57752024-03-22med@iucr.orgresearch papershttps://creativecommons.org/licenses/by/4.0/31600-5775Quantifying bunch-mode influence on photon-counting detectors at SPring-8
http://scripts.iucr.org/cgi-bin/paper?gy5059
Count-loss characteristics of photon-counting 2D detectors are demonstrated for eight bunch-modes at SPring-8 through Monte Carlo simulations. As an indicator, the effective maximum count rate was introduced to signify the X-ray intensity that the detector can count with a linearity of 1% or better after applying a count-loss correction in each bunch-mode. The effective maximum count rate is revealed to vary depending on the bunch-mode and the intrinsic dead time of the detectors, ranging from 0.012 to 0.916 Mcps (megacounts per second) for a 120 ns dead time, 0.009 to 0.807 Mcps for a 0.5 µs dead time and 0.020 to 0.273 Mcps for a 3 µs intrinsic detector dead time. Even with equal-interval bunch-modes at SPring-8, the effective maximum count rate does not exceed 1 Mcps pixel−1. In other words, to obtain data with a linearity better than 1%, the maximum intensity of X-rays entering the detector should be reduced to 1 Mcps pixel−1 or less, and, in some cases, even lower, depending on the bunch-mode. When applying count-loss correction using optimized dead times tailored to each bunch-mode, the effective maximum count rate exceeds the values above. However, differences in the effective maximum count rate due to bunch-modes persist. Users of photon-counting 2D detectors are encouraged to familiarize themselves with the count-loss characteristics dependent on bunch-mode, and to conduct experiments accordingly. In addition, when designing the time structure of bunch-modes at synchrotron radiation facilities, it is essential to take into account the impact on experiments using photon-counting 2D detectors.textCount-loss characteristics of photon-counting 2D detectors are demonstrated for eight bunch-modes at SPring-8 through Monte Carlo simulations. As an indicator, the effective maximum count rate was introduced to signify the X-ray intensity that the detector can count with a linearity of 1% or better after applying a count-loss correction in each bunch-mode. The effective maximum count rate is revealed to vary depending on the bunch-mode and the intrinsic dead time of the detectors, ranging from 0.012 to 0.916 Mcps (megacounts per second) for a 120 ns dead time, 0.009 to 0.807 Mcps for a 0.5 µs dead time and 0.020 to 0.273 Mcps for a 3 µs intrinsic detector dead time. Even with equal-interval bunch-modes at SPring-8, the effective maximum count rate does not exceed 1 Mcps pixel−1. In other words, to obtain data with a linearity better than 1%, the maximum intensity of X-rays entering the detector should be reduced to 1 Mcps pixel−1 or less, and, in some cases, even lower, depending on the bunch-mode. When applying count-loss correction using optimized dead times tailored to each bunch-mode, the effective maximum count rate exceeds the values above. However, differences in the effective maximum count rate due to bunch-modes persist. Users of photon-counting 2D detectors are encouraged to familiarize themselves with the count-loss characteristics dependent on bunch-mode, and to conduct experiments accordingly. In addition, when designing the time structure of bunch-modes at synchrotron radiation facilities, it is essential to take into account the impact on experiments using photon-counting 2D detectors.urn:issn:1600-5775text/htmlThe effects of SPring-8 bunch-modes on the count-loss features of photon-counting detectors and effective maximum count rates are discussed.2024-02-16PHOTON-COUNTING 2D DETECTORS; COUNT-LOSS; BUNCH-MODES; MAXIMUN COUNT RATES; RATE CORRECTIONQuantifying bunch-mode influence on photon-counting detectors at SPring-8International Union of CrystallographyImai, Y.Hatsui, T.doi:10.1107/S1600577524001085enhttps://creativecommons.org/licenses/by/4.0/March 2024Journal of Synchrotron Radiation313021600-57752024-02-16med@iucr.orgresearch papers295https://creativecommons.org/licenses/by/4.0/21600-5775Determination of optimal experimental conditions for accurate 3D reconstruction of the magnetization vector via XMCD-PEEM
http://scripts.iucr.org/cgi-bin/paper?gy5060
This work presents a detailed analysis of the performance of X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) as a tool for vector reconstruction of magnetization. For this, 360° domain wall ring structures which form in a synthetic antiferromagnet are chosen as the model to conduct the quantitative analysis. An assessment is made of how the quality of the results is affected depending on the number of projections that are involved in the reconstruction process, as well as their angular distribution. For this a self-consistent error metric is developed which allows an estimation of the optimum azimuthal rotation angular range and number of projections. This work thus proposes XMCD-PEEM as a powerful tool for vector imaging of complex 3D magnetic structures.textThis work presents a detailed analysis of the performance of X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) as a tool for vector reconstruction of magnetization. For this, 360° domain wall ring structures which form in a synthetic antiferromagnet are chosen as the model to conduct the quantitative analysis. An assessment is made of how the quality of the results is affected depending on the number of projections that are involved in the reconstruction process, as well as their angular distribution. For this a self-consistent error metric is developed which allows an estimation of the optimum azimuthal rotation angular range and number of projections. This work thus proposes XMCD-PEEM as a powerful tool for vector imaging of complex 3D magnetic structures.urn:issn:1600-5775text/htmlThe performance of X-ray magnetic circular dichroism photoemission electron microscopy for vector imaging of complex three-dimensional magnetic textures is investigated.2024-02-19THREE-DIMENSIONAL MAGNETIC VECTOR RECONSTRUCTION; X-RAY MAGNETIC CIRCULAR DICHROISM PHOTO-EMISSION ELECTRON MICROSCOPY; XMCD-PEEM; NANOMAGNETISM; 360DEGREES DOMAIN WALL RINGSDetermination of optimal experimental conditions for accurate 3D reconstruction of the magnetization vector via XMCD-PEEMInternational Union of CrystallographyCascales-Sandoval, M.A.Hierro-Rodriguez, A.Ruiz-Gómez, S.Skoric, L.Donnelly, C.Niño, M.A.McGrouther, D.McVitie, S.Flewett, S.Jaouen, N.Belkhou, R.Foerster, M.Fernandez-Pacheco, A.doi:10.1107/S1600577524001073enhttps://creativecommons.org/licenses/by/4.0/1600-5775336research papershttps://creativecommons.org/licenses/by/4.0/22024-02-191600-5775med@iucr.orgJournal of Synchrotron Radiation31342March 2024ForMAX – a beamline for multiscale and multimodal structural characterization of hierarchical materials
http://scripts.iucr.org/cgi-bin/paper?rv5175
The ForMAX beamline at the MAX IV Laboratory provides multiscale and multimodal structural characterization of hierarchical materials in the nanometre to millimetre range by combining small- and wide-angle X-ray scattering with full-field microtomography. The modular design of the beamline is optimized for easy switching between different experimental modalities. The beamline has a special focus on the development of novel fibrous materials from forest resources, but it is also well suited for studies within, for example, food science and biomedical research.textThe ForMAX beamline at the MAX IV Laboratory provides multiscale and multimodal structural characterization of hierarchical materials in the nanometre to millimetre range by combining small- and wide-angle X-ray scattering with full-field microtomography. The modular design of the beamline is optimized for easy switching between different experimental modalities. The beamline has a special focus on the development of novel fibrous materials from forest resources, but it is also well suited for studies within, for example, food science and biomedical research.urn:issn:1600-5775text/htmlForMAX is a new beamline at the MAX IV Laboratory, providing multiscale and multimodal structural characterization by combining small- and wide-angle X-ray scattering with full-field tomographic imaging.2024-02-22MULTISCALE STRUCTURAL CHARACTERIZATION; MULTIMODAL STRUCTURAL CHARACTERIZATION; HIERARCHICAL MATERIALS; FIBROUS MATERIALS; SMALL-ANGLE X-RAY SCATTERING; WIDE-ANGLE X-RAY SCATTERING; FULL-FIELD X-RAY MICROTOMOGRAPHYForMAX – a beamline for multiscale and multimodal structural characterization of hierarchical materialsInternational Union of CrystallographyNygård, K.McDonald, S.A.González, J.B.Haghighat, V.Appel, C.Larsson, E.Ghanbari, R.Viljanen, M.Silva, J.Malki, S.Li, Y.Silva, V.Weninger, C.Engelmann, F.Jeppsson, T.Felcsuti, G.Rosén, T.Gordeyeva, K.Söderberg, L.D.Dierks, H.Zhang, Y.Yao, Z.Yang, R.Asimakopoulou, E.M.Rogalinski, J.K.Wallentin, J.Villanueva-Perez, P.Krüger, R.Dreier, T.Bech, M.Liebi, M.Bek, M.Kádár, R.Terry, A.E.Tarawneh, H.Ilinski, P.Malmqvist, J.Cerenius, Y.doi:10.1107/S1600577524001048enhttps://creativecommons.org/licenses/by/4.0/1600-57752https://creativecommons.org/licenses/by/4.0/363beamlinesmed@iucr.org2024-02-221600-577537731Journal of Synchrotron RadiationMarch 2024Novel correction procedure for compensating thermal contraction errors in the measurement of the magnetic field of superconducting undulator coils in a liquid helium cryostat
http://scripts.iucr.org/cgi-bin/paper?wz5037
Superconducting undulators (SCUs) can offer a much higher on-axis undulator field than state-of-the-art cryogenic permanent-magnet undulators with the same period and vacuum gap. The development of shorter-period and high-field SCUs would allow the free-electron laser and synchrotron radiation source community to reduce both the length of undulators and the dimensions of the accelerator. Magnetic measurements are essential for characterizing the magnetic field quality of undulators for operation in a modern light source. Hall probe scanning is so far the most mature technique for local field characterization of undulators. This article focuses on the systematic error caused by thermal contraction that influences Hall probe measurements carried out in a liquid helium cryostat. A novel procedure, based on the redundant measurement of the magnetic field using multiple Hall probes at known relative distance, is introduced for the correction of such systematic error.textSuperconducting undulators (SCUs) can offer a much higher on-axis undulator field than state-of-the-art cryogenic permanent-magnet undulators with the same period and vacuum gap. The development of shorter-period and high-field SCUs would allow the free-electron laser and synchrotron radiation source community to reduce both the length of undulators and the dimensions of the accelerator. Magnetic measurements are essential for characterizing the magnetic field quality of undulators for operation in a modern light source. Hall probe scanning is so far the most mature technique for local field characterization of undulators. This article focuses on the systematic error caused by thermal contraction that influences Hall probe measurements carried out in a liquid helium cryostat. A novel procedure, based on the redundant measurement of the magnetic field using multiple Hall probes at known relative distance, is introduced for the correction of such systematic error.urn:issn:1600-5775text/htmlA novel correction procedure, for compensating thermal contraction errors in the measurement of the magnetic field of superconducting undulator coils in a liquid helium cryostat by using measurements made with multiple Hall probes placed at fixed distance, is proposed. The effectiveness and limitations of the correction procedure are validated by numerical simulations.2024-02-22SUPERCONDUCTING UNDULATORS; FEL; MAGNETIC FIELD MEASUREMENT; CRYOSTAT; DATA ANALYSISNovel correction procedure for compensating thermal contraction errors in the measurement of the magnetic field of superconducting undulator coils in a liquid helium cryostatInternational Union of CrystallographyMarchetti, B.Baader, J.Casalbuoni, S.Yakopov, G.Yakopov, M.doi:10.1107/S1600577524000808enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/2research papers282med@iucr.org1600-57752024-02-22March 202431Journal of Synchrotron Radiation294Optimization of synchrotron radiation parameters using swarm intelligence and evolutionary algorithms
http://scripts.iucr.org/cgi-bin/paper?ay5627
Alignment of each optical element at a synchrotron beamline takes days, even weeks, for each experiment costing valuable beam time. Evolutionary algorithms (EAs), efficient heuristic search methods based on Darwinian evolution, can be utilized for multi-objective optimization problems in different application areas. In this study, the flux and spot size of a synchrotron beam are optimized for two different experimental setups including optical elements such as lenses and mirrors. Calculations were carried out with the X-ray Tracer beamline simulator using swarm intelligence (SI) algorithms and for comparison the same setups were optimized with EAs. The EAs and SI algorithms used in this study for two different experimental setups are the Genetic Algorithm (GA), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC). While one of the algorithms optimizes the lens position, the other focuses on optimizing the focal distances of Kirkpatrick–Baez mirrors. First, mono-objective evolutionary algorithms were used and the spot size or flux values checked separately. After comparison of mono-objective algorithms, the multi-objective evolutionary algorithm NSGA-II was run for both objectives – minimum spot size and maximum flux. Every algorithm configuration was run several times for Monte Carlo simulations since these processes generate random solutions and the simulator also produces solutions that are stochastic. The results show that the PSO algorithm gives the best values over all setups.textAlignment of each optical element at a synchrotron beamline takes days, even weeks, for each experiment costing valuable beam time. Evolutionary algorithms (EAs), efficient heuristic search methods based on Darwinian evolution, can be utilized for multi-objective optimization problems in different application areas. In this study, the flux and spot size of a synchrotron beam are optimized for two different experimental setups including optical elements such as lenses and mirrors. Calculations were carried out with the X-ray Tracer beamline simulator using swarm intelligence (SI) algorithms and for comparison the same setups were optimized with EAs. The EAs and SI algorithms used in this study for two different experimental setups are the Genetic Algorithm (GA), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC). While one of the algorithms optimizes the lens position, the other focuses on optimizing the focal distances of Kirkpatrick–Baez mirrors. First, mono-objective evolutionary algorithms were used and the spot size or flux values checked separately. After comparison of mono-objective algorithms, the multi-objective evolutionary algorithm NSGA-II was run for both objectives – minimum spot size and maximum flux. Every algorithm configuration was run several times for Monte Carlo simulations since these processes generate random solutions and the simulator also produces solutions that are stochastic. The results show that the PSO algorithm gives the best values over all setups.urn:issn:1600-5775text/htmlDifferent algorithms were tested on a synchrotron beamline. Results show that the swarm intelligence algorithm and the particle swarm optimization algorithm perform better than previous algorithms.2024-02-22SYNCHROTRON BEAMLINES; KB MIRRORS; BE COMPOUND REFRACTIVE LENSES; SWARM INTELLIGENCE; EVOLUTIONARY ALGORITHMS; MULTI-OBJECTIVE OPTIMIZATIONOptimization of synchrotron radiation parameters using swarm intelligence and evolutionary algorithmsInternational Union of CrystallographyKaraca, A.S.Bostanci, E.Ketenoglu, D.Harder, M.Canbay, A.C.Ketenoglu, B.Eren, E.Aydin, A.Yin, Z.Guzel, M.S.Martins, M.doi:10.1107/S1600577524000717enhttps://creativecommons.org/licenses/by/4.0/computer programs4202https://creativecommons.org/licenses/by/4.0/1600-577542931Journal of Synchrotron RadiationMarch 20242024-02-221600-5775med@iucr.orgA differentiable simulation package for performing inference of synchrotron-radiation-based diagnostics
http://scripts.iucr.org/cgi-bin/paper?tv5053
The direction of particle accelerator development is ever-increasing beam quality, currents and repetition rates. This poses a challenge to traditional diagnostics that directly intercept the beam due to the mutual destruction of both the beam and the diagnostic. An alternative approach is to infer beam parameters non-invasively from the synchrotron radiation emitted in bending magnets. However, inferring the beam distribution from a measured radiation pattern is a complex and computationally expensive task. To address this challenge we present SYRIPY (SYnchrotron Radiation In PYthon), a software package intended as a tool for performing inference of synchrotron-radiation-based diagnostics. SYRIPY has been developed using PyTorch, which makes it both differentiable and able to leverage the high performance of GPUs, two vital characteristics for performing statistical inference. The package consists of three modules: a particle tracker, Lienard–Wiechert solver and Fourier optics propagator, allowing start-to-end simulation of synchrotron radiation detection to be carried out. SYRIPY has been benchmarked against SRW, the prevalent numerical package in the field, showing good agreement and up to a 50× speed improvement. Finally, we have demonstrated how SYRIPY can be used to perform Bayesian inference of beam parameters using stochastic variational inference.textThe direction of particle accelerator development is ever-increasing beam quality, currents and repetition rates. This poses a challenge to traditional diagnostics that directly intercept the beam due to the mutual destruction of both the beam and the diagnostic. An alternative approach is to infer beam parameters non-invasively from the synchrotron radiation emitted in bending magnets. However, inferring the beam distribution from a measured radiation pattern is a complex and computationally expensive task. To address this challenge we present SYRIPY (SYnchrotron Radiation In PYthon), a software package intended as a tool for performing inference of synchrotron-radiation-based diagnostics. SYRIPY has been developed using PyTorch, which makes it both differentiable and able to leverage the high performance of GPUs, two vital characteristics for performing statistical inference. The package consists of three modules: a particle tracker, Lienard–Wiechert solver and Fourier optics propagator, allowing start-to-end simulation of synchrotron radiation detection to be carried out. SYRIPY has been benchmarked against SRW, the prevalent numerical package in the field, showing good agreement and up to a 50× speed improvement. Finally, we have demonstrated how SYRIPY can be used to perform Bayesian inference of beam parameters using stochastic variational inference.urn:issn:1600-5775text/htmlSYRIPY (SYnchrotron Radiation In PYthon) is a new package for modelling the production and propagation of synchrotron radiation. The package has been developed using PyTorch, making it both differentiable and able to leverage the high performance of GPUs.2024-02-16ACCELERATOR DIAGNOSTICS; DIFFERENTIABLE SIMULATIONS; MACHINE LEARNINGA differentiable simulation package for performing inference of synchrotron-radiation-based diagnosticsInternational Union of CrystallographyWatt, R.O'Shea, B.doi:10.1107/S1600577524000663enhttps://creativecommons.org/licenses/by/4.0/1600-57752024-02-16med@iucr.orgMarch 202441931Journal of Synchrotron Radiation1600-5775computer programs4092https://creativecommons.org/licenses/by/4.0/The role of carboxylate ligand orbitals in the breathing dynamics of a metal-organic framework by resonant X-ray emission spectroscopy
http://scripts.iucr.org/cgi-bin/paper?iy5002
Metal-organic frameworks (MOFs) exhibit structural flexibility induced by temperature and guest adsorption, as demonstrated in the structural breathing transition in certain MOFs between narrow-pore and large-pore phases. Soft modes were suggested to entropically drive such pore breathing through enhanced vibrational dynamics at high temperatures. In this work, oxygen K-edge resonant X-ray emission spectroscopy of the MIL-53(Al) MOF was performed to selectively probe the electronic perturbation accompanying pore breathing dynamics at the ligand carboxylate site for metal–ligand interaction. It was observed that the temperature-induced vibrational dynamics involves switching occupancy between antisymmetric and symmetric configurations of the carboxylate oxygen lone pair orbitals, through which electron density around carboxylate oxygen sites is redistributed and metal–ligand interactions are tuned. In turn, water adsorption involves an additional perturbation of π orbitals not observed in the structural change solely induced by temperature.textMetal-organic frameworks (MOFs) exhibit structural flexibility induced by temperature and guest adsorption, as demonstrated in the structural breathing transition in certain MOFs between narrow-pore and large-pore phases. Soft modes were suggested to entropically drive such pore breathing through enhanced vibrational dynamics at high temperatures. In this work, oxygen K-edge resonant X-ray emission spectroscopy of the MIL-53(Al) MOF was performed to selectively probe the electronic perturbation accompanying pore breathing dynamics at the ligand carboxylate site for metal–ligand interaction. It was observed that the temperature-induced vibrational dynamics involves switching occupancy between antisymmetric and symmetric configurations of the carboxylate oxygen lone pair orbitals, through which electron density around carboxylate oxygen sites is redistributed and metal–ligand interactions are tuned. In turn, water adsorption involves an additional perturbation of π orbitals not observed in the structural change solely induced by temperature.urn:issn:1600-5775text/htmlOrbital occupancy of the ligand carboxylate in-plane lone pair orbitals modulates the vibrational dynamics of certain breathing modes responsible for the structural phase transition of a carboxylate metal-organic framework.2024-02-16RESONANT X-RAY EMISSION SPECTROSCOPY; PHASE TRANSITION; METAL-ORGANIC FRAMEWORKThe role of carboxylate ligand orbitals in the breathing dynamics of a metal-organic framework by resonant X-ray emission spectroscopyInternational Union of CrystallographyUgalino, R.Yamazoe, K.Miyawaki, J.Kiuchi, H.Kurahashi, N.Kosegawa, Y.Harada, Y.doi:10.1107/S1600577524000584enhttps://creativecommons.org/licenses/by/4.0/2https://creativecommons.org/licenses/by/4.0/research papers2171600-577522131Journal of Synchrotron RadiationMarch 2024med@iucr.org2024-02-161600-5775Investigation of structural and reflective characteristics of short-period Mo/B4C multilayer X-ray mirrors
http://scripts.iucr.org/cgi-bin/paper?ay5621
The results of a study of the structural and reflective characteristics of short-period multilayer X-ray mirrors based on Mo/B4C at wavelengths 1.54 Å, 9.89 Å and 17.59 Å are presented. The period of the samples varied in the range 8–35 Å. The average widths of the interfaces were ∼3.5 and 2.2 Å at one and the other boundaries, with a tendency for weak growth with any decrease in the period. The interlayer roughness was ∼1 Å. The research results indicate promising prospects for the use of multilayer Mo/B4C mirrors for synchrotron applications.textThe results of a study of the structural and reflective characteristics of short-period multilayer X-ray mirrors based on Mo/B4C at wavelengths 1.54 Å, 9.89 Å and 17.59 Å are presented. The period of the samples varied in the range 8–35 Å. The average widths of the interfaces were ∼3.5 and 2.2 Å at one and the other boundaries, with a tendency for weak growth with any decrease in the period. The interlayer roughness was ∼1 Å. The research results indicate promising prospects for the use of multilayer Mo/B4C mirrors for synchrotron applications.urn:issn:1600-5775text/htmlShort-period Mo/B4C multilayer mirrors are shown to be extremely promising for use in synchrotron applications.2024-02-09X-RAY MULTILAYER MIRRORS; SYNCHROTRON APPLICATIONS; X-RAY MONOCHROMATORSInvestigation of structural and reflective characteristics of short-period Mo/B4C multilayer X-ray mirrorsInternational Union of CrystallographyShaposhnikov, R.Polkovnikov, V.Garakhin, S.Vainer, Y.Chkhalo, N.Smertin, R.Durov, K.Glushkov, E.Yakunin, S.Borisov, M.doi:10.1107/S1600577524000419enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org2024-02-091600-577527531Journal of Synchrotron RadiationMarch 20241600-57752https://creativecommons.org/licenses/by/4.0/research papers268Grazing-incidence synchrotron radiation diffraction studies on irradiated Ce-doped and pristine Y-stabilized ZrO2 at the Rossendorf beamline
http://scripts.iucr.org/cgi-bin/paper?yi5147
In this work, Ce-doped yttria-stabilized zirconia (YSZ) and pure YSZ phases were subjected to irradiation with 14 MeV Au ions. Irradiation studies were performed to simulate long-term structural and microstructural damage due to self-irradiation in YSZ phases hosting alpha-active radioactive species. It was found that both the Ce-doped YSZ and the YSZ phases had a reasonable tolerance to irradiation at high ion fluences and the bulk crystallinity was well preserved. Nevertheless, local microstrain increased in all compounds under study after irradiation, with the Ce-doped phases being less affected than pure YSZ. Doping with cerium ions increased the microstructural stability of YSZ phases through a possible reduction in the mobility of oxygen atoms, which limits the formation of structural defects. Doping of YSZ with tetravalent actinide elements is expected to have a similar effect. Thus, YSZ phases are promising for the safe long-term storage of radioactive elements. Using synchrotron radiation diffraction, measurements of the thin irradiated layers of the Ce-YSZ and YSZ samples were performed in grazing incidence (GI) mode. A corresponding module for measurements in GI mode was developed at the Rossendorf Beamline and relevant technical details for sample alignment and data collection are also presented.textIn this work, Ce-doped yttria-stabilized zirconia (YSZ) and pure YSZ phases were subjected to irradiation with 14 MeV Au ions. Irradiation studies were performed to simulate long-term structural and microstructural damage due to self-irradiation in YSZ phases hosting alpha-active radioactive species. It was found that both the Ce-doped YSZ and the YSZ phases had a reasonable tolerance to irradiation at high ion fluences and the bulk crystallinity was well preserved. Nevertheless, local microstrain increased in all compounds under study after irradiation, with the Ce-doped phases being less affected than pure YSZ. Doping with cerium ions increased the microstructural stability of YSZ phases through a possible reduction in the mobility of oxygen atoms, which limits the formation of structural defects. Doping of YSZ with tetravalent actinide elements is expected to have a similar effect. Thus, YSZ phases are promising for the safe long-term storage of radioactive elements. Using synchrotron radiation diffraction, measurements of the thin irradiated layers of the Ce-YSZ and YSZ samples were performed in grazing incidence (GI) mode. A corresponding module for measurements in GI mode was developed at the Rossendorf Beamline and relevant technical details for sample alignment and data collection are also presented.urn:issn:1600-5775text/htmlIrradiated Ce-doped yttria-stabilized zirconia (YSZ) and pure YSZ phases were characterized using grazing incidence (GI) synchrotron radiation diffraction. A corresponding module for measurements in GI mode was developed at ROBL and relevant technical details of sample alignment and data collection are presented.2024-02-16YTTRIA-STABILIZED ZIRCONIA; IRRADIATION; SYNCHROTRON RADIATION; GRAZING INCIDENCE DIFFRACTION; MICROSTRAINGrazing-incidence synchrotron radiation diffraction studies on irradiated Ce-doped and pristine Y-stabilized ZrO2 at the Rossendorf beamlineInternational Union of CrystallographySvitlyk, V.Braga Ferreira dos Santos, L.Niessen, J.Gilson, S.Marquardt, J.Findeisen, S.Richter, S.Akhmadaliev, S.Huittinen, N.Hennig, C.doi:10.1107/S1600577524000304enhttps://creativecommons.org/licenses/by/4.0/beamlines355https://creativecommons.org/licenses/by/4.0/21600-5775Journal of Synchrotron Radiation31362March 20242024-02-161600-5775med@iucr.orgUltrashort large-bandwidth X-ray free-electron laser generation with a dielectric-lined waveguide
http://scripts.iucr.org/cgi-bin/paper?yi5145
Large-bandwidth pulses produced by cutting-edge X-ray free-electron lasers (FELs) are of great importance in research fields like material science and biology. In this paper, a new method to generate high-power ultrashort FEL pulses with tunable spectral bandwidth with spectral coherence using a dielectric-lined waveguide without interfering operation of linacs is proposed. By exploiting the passive and dephasingless wakefield at terahertz frequency excited by the beam, stable energy modulation can be achieved in the electron beam and large-bandwidth high-intensity soft X-ray radiation can be generated. Three-dimensional start-to-end simulations have been carried out and the results show that coherent radiation pulses with duration of a few femtoseconds and bandwidths ranging from 1.01% to 2.16% can be achieved by changing the undulator taper profile.textLarge-bandwidth pulses produced by cutting-edge X-ray free-electron lasers (FELs) are of great importance in research fields like material science and biology. In this paper, a new method to generate high-power ultrashort FEL pulses with tunable spectral bandwidth with spectral coherence using a dielectric-lined waveguide without interfering operation of linacs is proposed. By exploiting the passive and dephasingless wakefield at terahertz frequency excited by the beam, stable energy modulation can be achieved in the electron beam and large-bandwidth high-intensity soft X-ray radiation can be generated. Three-dimensional start-to-end simulations have been carried out and the results show that coherent radiation pulses with duration of a few femtoseconds and bandwidths ranging from 1.01% to 2.16% can be achieved by changing the undulator taper profile.urn:issn:1600-5775text/htmlUltrashort large-bandwidth X-ray free-electron laser generation is proposed using a dielectric-lined waveguide. With this modulation scheme through strong terahertz wakefield self-excited, a cheap and flexible large-bandwidth operation mode is researched for free-electron-laser complexes.2024-02-09FREE-ELECTRON LASER; DIELECTRIC WAKEFIELD; LARGE-BANDWIDTH X-RAY; TERAHERTZUltrashort large-bandwidth X-ray free-electron laser generation with a dielectric-lined waveguideInternational Union of CrystallographyLiu, Y.Wang, Z.Tu, L.Feng, C.Zhao, Z.doi:10.1107/S1600577524000249enhttps://creativecommons.org/licenses/by/4.0/March 202425131Journal of Synchrotron Radiationmed@iucr.org1600-57752024-02-092https://creativecommons.org/licenses/by/4.0/243research papers1600-5775Sub-micrometre focusing of intense 100 keV X-rays with multilayer reflective optics
http://scripts.iucr.org/cgi-bin/paper?ye5038
A high-flux sub-micrometre focusing system was constructed using multilayer focusing mirrors in Kirkpatrick–Baez geometry for 100 keV X-rays. The focusing mirror system had a wide bandwidth of 5% and a high peak reflectivity of 74%. Performance was evaluated at the undulator beamline BL05XU of SPring-8, which produced an intense 100 keV X-ray beam with a bandwidth of 1%. When the light source was focused directly in both vertical and horizontal directions, the beam size was measured to be 0.32 µm (V) × 5.3 µm (H) with a flux of 1 × 1012 photons s−1. However, when a limited horizontal slit was used to form a secondary source, the focusing beam size decreased to 0.25 µm (V) × 0.26 µm (H) with a flux of 6 × 1010 photons s−1. The 200 nm line and space patterns of a Siemens star chart made of tantalum were clearly resolved by the absorption contrast of the focused beam. This 100 keV focusing system is applicable to various fields of nondestructive analyses with sub-micrometre resolutions.textA high-flux sub-micrometre focusing system was constructed using multilayer focusing mirrors in Kirkpatrick–Baez geometry for 100 keV X-rays. The focusing mirror system had a wide bandwidth of 5% and a high peak reflectivity of 74%. Performance was evaluated at the undulator beamline BL05XU of SPring-8, which produced an intense 100 keV X-ray beam with a bandwidth of 1%. When the light source was focused directly in both vertical and horizontal directions, the beam size was measured to be 0.32 µm (V) × 5.3 µm (H) with a flux of 1 × 1012 photons s−1. However, when a limited horizontal slit was used to form a secondary source, the focusing beam size decreased to 0.25 µm (V) × 0.26 µm (H) with a flux of 6 × 1010 photons s−1. The 200 nm line and space patterns of a Siemens star chart made of tantalum were clearly resolved by the absorption contrast of the focused beam. This 100 keV focusing system is applicable to various fields of nondestructive analyses with sub-micrometre resolutions.urn:issn:1600-5775text/htmlA high-flux sub-micrometre focusing system for 100 keV X-rays using multilayer focusing mirrors was constructed and evaluated at the undulator beamline BL05XU of SPring-8.2024-02-22HIGH-ENERGY X-RAYS; 100 KEV X-RAYS; MULTILAYER MONOCHROMATORS; MULTILAYER FOCUSING MIRRORS; SCANNING TRANSMISSION IMAGINGSub-micrometre focusing of intense 100 keV X-rays with multilayer reflective opticsInternational Union of CrystallographyKoyama, T.Yumoto, H.Miura, T.Matsuzaki, Y.Yabashi, M.Ohashi, H.doi:10.1107/S1600577524000213enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/2research papers2761600-5775March 2024Journal of Synchrotron Radiation31281med@iucr.org1600-57752024-02-22Enhancing electrospray ionization efficiency for particle transmission through an aerodynamic lens stack
http://scripts.iucr.org/cgi-bin/paper?gy5055
This work investigates the performance of the electrospray aerosol generator at the European X-ray Free Electron Laser (EuXFEL). This generator is, together with an aerodynamic lens stack that transports the particles into the X-ray interaction vacuum chamber, the method of choice to deliver particles for single-particle coherent diffractive imaging (SPI) experiments at the EuXFEL. For these experiments to be successful, it is necessary to achieve high transmission of particles from solution into the vacuum interaction region. Particle transmission is highly dependent on efficient neutralization of the charged aerosol generated by the electrospray mechanism as well as the geometry in the vicinity of the Taylor cone. We report absolute particle transmission values for different neutralizers and geometries while keeping the conditions suitable for SPI experiments. Our findings reveal that a vacuum ultraviolet ionizer demonstrates a transmission efficiency approximately seven times greater than the soft X-ray ionizer used previously. Combined with an optimized orifice size on the counter electrode, we achieve >40% particle transmission from solution into the X-ray interaction region. These findings offer valuable insights for optimizing electrospray aerosol generator configurations and data rates for SPI experiments.textThis work investigates the performance of the electrospray aerosol generator at the European X-ray Free Electron Laser (EuXFEL). This generator is, together with an aerodynamic lens stack that transports the particles into the X-ray interaction vacuum chamber, the method of choice to deliver particles for single-particle coherent diffractive imaging (SPI) experiments at the EuXFEL. For these experiments to be successful, it is necessary to achieve high transmission of particles from solution into the vacuum interaction region. Particle transmission is highly dependent on efficient neutralization of the charged aerosol generated by the electrospray mechanism as well as the geometry in the vicinity of the Taylor cone. We report absolute particle transmission values for different neutralizers and geometries while keeping the conditions suitable for SPI experiments. Our findings reveal that a vacuum ultraviolet ionizer demonstrates a transmission efficiency approximately seven times greater than the soft X-ray ionizer used previously. Combined with an optimized orifice size on the counter electrode, we achieve >40% particle transmission from solution into the X-ray interaction region. These findings offer valuable insights for optimizing electrospray aerosol generator configurations and data rates for SPI experiments.urn:issn:1600-5775text/htmlWe investigate the performance of an electrospray aerosol generator at the European X-ray Free Electron Laser for single-particle coherent diffractive imaging. The findings highlight enhanced particle transmission efficiency with VUV ionization, larger orifice diameters, electric fields and 3D-printed twin-nozzle design, providing insights for optimizing aerosol injection in XFEL experiments.2024-02-02ELECTROSPRAY IONIZATION; AEROSOL INJECTION; AEROSOL NEUTRALIZATION; SINGLE-PARTICLE IMAGING; XFELSEnhancing electrospray ionization efficiency for particle transmission through an aerodynamic lens stackInternational Union of CrystallographyRafie-Zinedine, S.Varma Yenupuri, T.Worbs, L.Maia, F.R.N.C.Heymann, M.Schulz, J.Bielecki, J.doi:10.1107/S1600577524000158enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752024-02-02March 2024232Journal of Synchrotron Radiation311600-57752https://creativecommons.org/licenses/by/4.0/research papers222ProSPyX: software for post-processing images of X-ray ptychography with spectral capabilities
http://scripts.iucr.org/cgi-bin/paper?gy5057
X-ray ptychography is a coherent diffraction imaging technique based on acquiring multiple diffraction patterns obtained through the illumination of the sample at different partially overlapping probe positions. The diffraction patterns collected are used to retrieve the complex transmittivity function of the sample and the probe using a phase retrieval algorithm. Absorption or phase contrast images of the sample as well as the real and imaginary parts of the probe function can be obtained. Furthermore, X-ray ptychography can also provide spectral information of the sample from absorption or phase shift images by capturing multiple ptychographic projections at varying energies around the resonant energy of the element of interest. However, post-processing of the images is required to extract the spectra. To facilitate this, ProSPyX, a Python package that offers the analysis tools and a graphical user interface required to process spectral ptychography datasets, is presented. Using the PyQt5 Python open-source module for development and design, the software facilitates extraction of absorption and phase spectral information from spectral ptychographic datasets. It also saves the spectra in file formats compatible with other X-ray absorption spectroscopy data analysis software tools, streamlining integration into existing spectroscopic data analysis pipelines. To illustrate its capabilities, ProSPyX was applied to process the spectral ptychography dataset recently acquired on a nickel wire at the SWING beamline of the SOLEIL synchrotron.textX-ray ptychography is a coherent diffraction imaging technique based on acquiring multiple diffraction patterns obtained through the illumination of the sample at different partially overlapping probe positions. The diffraction patterns collected are used to retrieve the complex transmittivity function of the sample and the probe using a phase retrieval algorithm. Absorption or phase contrast images of the sample as well as the real and imaginary parts of the probe function can be obtained. Furthermore, X-ray ptychography can also provide spectral information of the sample from absorption or phase shift images by capturing multiple ptychographic projections at varying energies around the resonant energy of the element of interest. However, post-processing of the images is required to extract the spectra. To facilitate this, ProSPyX, a Python package that offers the analysis tools and a graphical user interface required to process spectral ptychography datasets, is presented. Using the PyQt5 Python open-source module for development and design, the software facilitates extraction of absorption and phase spectral information from spectral ptychographic datasets. It also saves the spectra in file formats compatible with other X-ray absorption spectroscopy data analysis software tools, streamlining integration into existing spectroscopic data analysis pipelines. To illustrate its capabilities, ProSPyX was applied to process the spectral ptychography dataset recently acquired on a nickel wire at the SWING beamline of the SOLEIL synchrotron.urn:issn:1600-5775text/htmlProSPyXis a Python intuitive graphical user interface that enables extraction of absorption and phase spectral information from spectral ptychographic datasets.2024-02-09PROSPYX; X-RAY SPECTRAL PTYCHOGRAPHY; GRAPHICAL USER INTERFACE; PYQT5; TOUPYProSPyX: software for post-processing images of X-ray ptychography with spectral capabilitiesInternational Union of CrystallographyBoudjehem, R.Kulow, A.Pérez, J.Gautier, E.Ould-chikh, S.Pairis, S.Hazemann, J.-L.da Silva, J.C.doi:10.1107/S160057752400016Xenhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752024-02-09March 202440831Journal of Synchrotron Radiation1600-57752https://creativecommons.org/licenses/by/4.0/computer programs399Image registration for in situ X-ray nano-imaging of a composite battery cathode with deformation
http://scripts.iucr.org/cgi-bin/paper?mo5272
The structural and chemical evolution of battery electrodes at the nanoscale plays an important role in affecting the cell performance. Nano-resolution X-ray microscopy has been demonstrated as a powerful technique for characterizing the evolution of battery electrodes under operating conditions with sensitivity to their morphology, compositional distribution and redox heterogeneity. In real-world batteries, the electrode could deform upon battery operation, causing challenges for the image registration which is necessary for several experimental modalities, e.g. XANES imaging. To address this challenge, this work develops a deep-learning-based method for automatic particle identification and tracking. This approach was not only able to facilitate image registration with good robustness but also allowed quantification of the degree of sample deformation. The effectiveness of the method was first demonstrated using synthetic datasets with known ground truth. The method was then applied to an experimental dataset collected on an operating lithium battery cell, revealing a high degree of intra- and interparticle chemical complexity in operating batteries.textThe structural and chemical evolution of battery electrodes at the nanoscale plays an important role in affecting the cell performance. Nano-resolution X-ray microscopy has been demonstrated as a powerful technique for characterizing the evolution of battery electrodes under operating conditions with sensitivity to their morphology, compositional distribution and redox heterogeneity. In real-world batteries, the electrode could deform upon battery operation, causing challenges for the image registration which is necessary for several experimental modalities, e.g. XANES imaging. To address this challenge, this work develops a deep-learning-based method for automatic particle identification and tracking. This approach was not only able to facilitate image registration with good robustness but also allowed quantification of the degree of sample deformation. The effectiveness of the method was first demonstrated using synthetic datasets with known ground truth. The method was then applied to an experimental dataset collected on an operating lithium battery cell, revealing a high degree of intra- and interparticle chemical complexity in operating batteries.urn:issn:1600-5775text/htmlA deep-learning-assisted image registration method is demonstrated for in situ X-ray nano-imaging of a composite battery cathode electrode with deformation. The method handles the challenges associated with electrode deformation by identifying and tracking isolated cathode particles separately. This approach could facilitate analysis of the correlation between intraparticle reaction heterogeneity and electrode deformation, which collectively affect the performance of real-world batteries.2024-02-01IMAGE REGISTRATION; TRANSMISSION X-RAY MICROSCOPY; BATTERY ELECTRODE DEFORMATION; CHEMICAL HETEROGENEITYImage registration for in situ X-ray nano-imaging of a composite battery cathode with deformationInternational Union of CrystallographySu, B.Qian, G.Gao, R.Tao, F.Zhang, L.Du, G.Deng, B.Pianetta, P.Liu, Y.doi:10.1107/S1600577524000146enhttps://creativecommons.org/licenses/by/4.0/1600-57752024-02-01med@iucr.orgMarch 202433531Journal of Synchrotron Radiation1600-5775research papers3282https://creativecommons.org/licenses/by/4.0/Open-source electrochemical cell for in situ X-ray absorption spectroscopy in transmission and fluorescence modes
http://scripts.iucr.org/cgi-bin/paper?vy5020
X-ray spectroscopy is a valuable technique for the study of many materials systems. Characterizing reactions in situ and operando can reveal complex reaction kinetics, which is crucial to understanding active site composition and reaction mechanisms. In this project, the design, fabrication and testing of an open-source and easy-to-fabricate electrochemical cell for in situ electrochemistry compatible with X-ray absorption spectroscopy in both transmission and fluorescence modes are accomplished via windows with large opening angles on both the upstream and downstream sides of the cell. Using a hobbyist computer numerical control machine and free 3D CAD software, anyone can make a reliable electrochemical cell using this design. Onion-like carbon nanoparticles, with a 1:3 iron-to-cobalt ratio, were drop-coated onto carbon paper for testing in situ X-ray absorption spectroscopy. Cyclic voltammetry of the carbon paper showed the expected behavior, with no increased ohmic drop, even in sandwiched cells. Chronoamperometry was used to apply 0.4 V versus reversible hydrogen electrode, with and without 15 min of oxygen purging to ensure that the electrochemical cell does not provide any artefacts due to gas purging. The XANES and EXAFS spectra showed no differences with and without oxygen, as expected at 0.4 V, without any artefacts due to gas purging. The development of this open-source electrochemical cell design allows for improved collection of in situ X-ray absorption spectroscopy data and enables researchers to perform both transmission and fluorescence simultaneously. It additionally addresses key practical considerations including gas purging, reduced ionic resistance and leak prevention.textX-ray spectroscopy is a valuable technique for the study of many materials systems. Characterizing reactions in situ and operando can reveal complex reaction kinetics, which is crucial to understanding active site composition and reaction mechanisms. In this project, the design, fabrication and testing of an open-source and easy-to-fabricate electrochemical cell for in situ electrochemistry compatible with X-ray absorption spectroscopy in both transmission and fluorescence modes are accomplished via windows with large opening angles on both the upstream and downstream sides of the cell. Using a hobbyist computer numerical control machine and free 3D CAD software, anyone can make a reliable electrochemical cell using this design. Onion-like carbon nanoparticles, with a 1:3 iron-to-cobalt ratio, were drop-coated onto carbon paper for testing in situ X-ray absorption spectroscopy. Cyclic voltammetry of the carbon paper showed the expected behavior, with no increased ohmic drop, even in sandwiched cells. Chronoamperometry was used to apply 0.4 V versus reversible hydrogen electrode, with and without 15 min of oxygen purging to ensure that the electrochemical cell does not provide any artefacts due to gas purging. The XANES and EXAFS spectra showed no differences with and without oxygen, as expected at 0.4 V, without any artefacts due to gas purging. The development of this open-source electrochemical cell design allows for improved collection of in situ X-ray absorption spectroscopy data and enables researchers to perform both transmission and fluorescence simultaneously. It additionally addresses key practical considerations including gas purging, reduced ionic resistance and leak prevention.urn:issn:1600-5775text/htmlAn economical and easy-to-fabricate electrochemical cell for in situ X-ray absorption spectroscopy was developed, fabricated, and used to obtain XANES and EXAFS data for a catalyst for the oxygen reduction reaction. The experiments were run with and without oxygen purging using an attachment that avoids interactions between bubbles and the working electrode, and X-ray absorption spectroscopy data were obtained under applied potential and with and without gas purging, showing the capabilities of this electrochemical cell for in situ experiments.2024-02-02ELECTROCHEMICAL CELLS FOR IN SITU XAS; EXAFS; ORR CATALYSTSOpen-source electrochemical cell for in situ X-ray absorption spectroscopy in transmission and fluorescence modesInternational Union of CrystallographyLopez-Astacio, H.Vargas-Perez, B.L.Del Valle-Perez, A.Pollock, C.J.Cunci, L.doi:10.1107/S1600577524000122enhttps://creativecommons.org/licenses/by/4.0/1600-5775322research papershttps://creativecommons.org/licenses/by/4.0/21600-57752024-02-02med@iucr.orgMarch 202431Journal of Synchrotron Radiation327Extracting the electronic structure signal from X-ray and electron scattering in the gas phase
http://scripts.iucr.org/cgi-bin/paper?ok5106
X-ray and electron scattering from free gas-phase molecules is examined using the independent atom model (IAM) and ab initio electronic structure calculations. The IAM describes the effect of the molecular geometry on the scattering, but does not account for the redistribution of valence electrons due to, for instance, chemical bonding. By examining the total, i.e. energy-integrated, scattering from three molecules, fluoroform (CHF3), 1,3-cyclohexadiene (C6H8) and naphthalene (C10H8), the effect of electron redistribution is found to predominantly reside at small-to-medium values of the momentum transfer (q ≤ 8 Å−1) in the scattering signal, with a maximum percent difference contribution at 2 ≤ q ≤ 3 Å−1. A procedure to determine the molecular geometry from the large-q scattering is demonstrated, making it possible to more clearly identify the deviation of the scattering from the IAM approximation at small and intermediate q and to provide a measure of the effect of valence electronic structure on the scattering signal.textX-ray and electron scattering from free gas-phase molecules is examined using the independent atom model (IAM) and ab initio electronic structure calculations. The IAM describes the effect of the molecular geometry on the scattering, but does not account for the redistribution of valence electrons due to, for instance, chemical bonding. By examining the total, i.e. energy-integrated, scattering from three molecules, fluoroform (CHF3), 1,3-cyclohexadiene (C6H8) and naphthalene (C10H8), the effect of electron redistribution is found to predominantly reside at small-to-medium values of the momentum transfer (q ≤ 8 Å−1) in the scattering signal, with a maximum percent difference contribution at 2 ≤ q ≤ 3 Å−1. A procedure to determine the molecular geometry from the large-q scattering is demonstrated, making it possible to more clearly identify the deviation of the scattering from the IAM approximation at small and intermediate q and to provide a measure of the effect of valence electronic structure on the scattering signal.urn:issn:1600-5775text/htmlA new method to determine molecular structure from large-angle scattering for X-ray and electron scattering from free gas-phase molecules is described.2024-02-22X-RAY SCATTERING; ELECTRON SCATTERING; GAS PHASE; AB INITIOExtracting the electronic structure signal from X-ray and electron scattering in the gas phaseInternational Union of CrystallographyNorthey, T.Kirrander, A.Weber, P.M.doi:10.1107/S1600577524000067enhttps://creativecommons.org/licenses/by/4.0/31131Journal of Synchrotron RadiationMarch 2024med@iucr.org2024-02-221600-57752https://creativecommons.org/licenses/by/4.0/303research papers1600-5775DOMAS: a data management software framework for advanced light sources
http://scripts.iucr.org/cgi-bin/paper?tv5052
In recent years, China's advanced light sources have entered a period of rapid construction and development. As modern X-ray detectors and data acquisition technologies advance, these facilities are expected to generate massive volumes of data annually, presenting significant challenges in data management and utilization. These challenges encompass data storage, metadata handling, data transfer and user data access. In response, the Data Organization Management Access Software (DOMAS) has been designed as a framework to address these issues. DOMAS encapsulates four fundamental modules of data management software, including metadata catalogue, metadata acquisition, data transfer and data service. For light source facilities, building a data management system only requires parameter configuration and minimal code development within DOMAS. This paper firstly discusses the development of advanced light sources in China and the associated demands and challenges in data management, prompting a reconsideration of data management software framework design. It then outlines the architecture of the framework, detailing its components and functions. Lastly, it highlights the application progress and effectiveness of DOMAS when deployed for the High Energy Photon Source (HEPS) and Beijing Synchrotron Radiation Facility (BSRF).textIn recent years, China's advanced light sources have entered a period of rapid construction and development. As modern X-ray detectors and data acquisition technologies advance, these facilities are expected to generate massive volumes of data annually, presenting significant challenges in data management and utilization. These challenges encompass data storage, metadata handling, data transfer and user data access. In response, the Data Organization Management Access Software (DOMAS) has been designed as a framework to address these issues. DOMAS encapsulates four fundamental modules of data management software, including metadata catalogue, metadata acquisition, data transfer and data service. For light source facilities, building a data management system only requires parameter configuration and minimal code development within DOMAS. This paper firstly discusses the development of advanced light sources in China and the associated demands and challenges in data management, prompting a reconsideration of data management software framework design. It then outlines the architecture of the framework, detailing its components and functions. Lastly, it highlights the application progress and effectiveness of DOMAS when deployed for the High Energy Photon Source (HEPS) and Beijing Synchrotron Radiation Facility (BSRF).urn:issn:1600-5775text/htmlDOMAS is a data management software framework specifically designed and developed for advanced light sources in China. It effectively tackles challenges related to data storage, metadata cataloguing, data transfer and data access.2024-02-01DATA MANAGEMENT; METADATA CATALOGUE; DATA TRANSFER; DATA SERVICEDOMAS: a data management software framework for advanced light sourcesInternational Union of CrystallographyHu, H.Lei, L.Wang, H.Zhuang, B.Zhang, R.Luo, Q.Sun, X.Qi, F.doi:10.1107/S1600577524000043enhttps://creativecommons.org/licenses/by/4.0/1600-5775research papers312https://creativecommons.org/licenses/by/4.0/22024-02-011600-5775med@iucr.orgJournal of Synchrotron Radiation31321March 2024xrdPlanner: exploring area detector geometries for powder diffraction and total scattering experiments
http://scripts.iucr.org/cgi-bin/paper?vl5018
xrdPlanner is a software package designed to aid in the planning and preparation of powder X-ray diffraction and total scattering beam times at synchrotron facilities. Many modern beamlines provide a flexible experimental setup and may have several different detectors available. In combination with a range of available X-ray energies, it often makes it difficult for the user to explore the available parameter space relevant for a given experiment prior to the scheduled beam time. xrdPlanner was developed to provide a fast and straightforward tool that allows users to visualize the accessible part of reciprocal space of their experiment at a given combination of photon energy and detector geometry. To plan and communicate the necessary geometry not only saves time but also helps the beamline staff to prepare and accommodate for an experiment. The program is tailored toward powder X-ray diffraction and total scattering experiments but may also be useful for other experiments that rely on an area detector and for which detector placement and achievable momentum-transfer range are important experimental parameters.textxrdPlanner is a software package designed to aid in the planning and preparation of powder X-ray diffraction and total scattering beam times at synchrotron facilities. Many modern beamlines provide a flexible experimental setup and may have several different detectors available. In combination with a range of available X-ray energies, it often makes it difficult for the user to explore the available parameter space relevant for a given experiment prior to the scheduled beam time. xrdPlanner was developed to provide a fast and straightforward tool that allows users to visualize the accessible part of reciprocal space of their experiment at a given combination of photon energy and detector geometry. To plan and communicate the necessary geometry not only saves time but also helps the beamline staff to prepare and accommodate for an experiment. The program is tailored toward powder X-ray diffraction and total scattering experiments but may also be useful for other experiments that rely on an area detector and for which detector placement and achievable momentum-transfer range are important experimental parameters.urn:issn:1600-5775text/htmlxrdPlanner is a software designed to assist in the planning of powder X-ray diffraction and total scattering experiments at synchrotron facilities. It provides a straightforward visualization of projected resolution intervals at different combinations of photon energy and detector geometry, and focus is put on an intuitive and fast presentation to facilitate live exploration of the available parameter space.2024-02-02X-RAY DIFFRACTION; X-RAY SCATTERING; SYNCHROTRON FACILITIES; SOFTWARE TOOLS; EXPERIMENT PLANNINGxrdPlanner: exploring area detector geometries for powder diffraction and total scattering experimentsInternational Union of CrystallographyKrause, L.Gjørup, F.H.Jørgensen, M.R.V.doi:10.1107/S1600577523011086enhttps://creativecommons.org/licenses/by/4.0/March 2024Journal of Synchrotron Radiation31398med@iucr.org1600-57752024-02-02https://creativecommons.org/licenses/by/4.0/2computer programs3941600-5775Submillisecond in situ X-ray diffraction measurement system with changing temperature and pressure using diamond anvil cells at BL10XU/SPring-8
http://scripts.iucr.org/cgi-bin/paper?vy5018
Recently, there has been a high demand for elucidating kinetics and visualizing reaction processes under extreme dynamic conditions, such as chemical reactions under meteorite impact conditions, structural changes under nonequilibrium conditions, and in situ observations of dynamic changes. To accelerate material science studies and Earth science fields under dynamic conditions, a submillisecond in situ X-ray diffraction measurement system has been developed using a diamond anvil cell to observe reaction processes under rapidly changing pressure and temperature conditions replicating extreme dynamic conditions. The development and measurements were performed at the high-pressure beamline BL10XU/SPring-8 by synchronizing a high-speed hybrid pixel array detector, laser heating and temperature measurement system, and gas-pressure control system that enables remote and rapid pressure changes using the diamond anvil cell. The synchronized system enabled momentary heating and rapid cooling experiments up to 5000 K via laser heating as well as the visualization of structural changes in high-pressure samples under extreme dynamic conditions during high-speed pressure changes.textRecently, there has been a high demand for elucidating kinetics and visualizing reaction processes under extreme dynamic conditions, such as chemical reactions under meteorite impact conditions, structural changes under nonequilibrium conditions, and in situ observations of dynamic changes. To accelerate material science studies and Earth science fields under dynamic conditions, a submillisecond in situ X-ray diffraction measurement system has been developed using a diamond anvil cell to observe reaction processes under rapidly changing pressure and temperature conditions replicating extreme dynamic conditions. The development and measurements were performed at the high-pressure beamline BL10XU/SPring-8 by synchronizing a high-speed hybrid pixel array detector, laser heating and temperature measurement system, and gas-pressure control system that enables remote and rapid pressure changes using the diamond anvil cell. The synchronized system enabled momentary heating and rapid cooling experiments up to 5000 K via laser heating as well as the visualization of structural changes in high-pressure samples under extreme dynamic conditions during high-speed pressure changes.urn:issn:1600-5775text/htmlA submillisecond X-ray diffraction measurement system targeted at microscopic samples in a diamond anvil cell has been developed at BL10XU/SPring-8. This system has enabled the visualization of structural changes of high-pressure samples in the diamond anvil cell during instantaneous heating and quenching experiments combined with laser heating and during instantaneous compression and decompression experiments using a two-line gas-pressure control system, with a resolution in the submillisecond range.2024-02-19DIAMOND ANVIL CELLS; X-RAY DIFFRACTION; IN SITU TIME-RESOLVED MEASUREMENT; BEAMLINESSubmillisecond in situ X-ray diffraction measurement system with changing temperature and pressure using diamond anvil cells at BL10XU/SPring-8International Union of CrystallographyKawaguchi-Imada, S.Sinmyo, R.Ohta, K.Kawaguchi, S.Kobayashi, T.doi:10.1107/S1600577523010974enhttps://creativecommons.org/licenses/by/4.0/March 202435431Journal of Synchrotron Radiationmed@iucr.org1600-57752024-02-192https://creativecommons.org/licenses/by/4.0/343beamlines1600-5775A new modular framework for high-level application development at HEPS
http://scripts.iucr.org/cgi-bin/paper?tv5051
As a representative of the fourth-generation light sources, the High Energy Photon Source (HEPS) in Beijing, China, utilizes a multi-bend achromat lattice to obtain an approximately 100 times emittance reduction compared with third-generation light sources. New technologies bring new challenges to operate the storage ring. In order to meet the beam commissioning requirements of HEPS, a new framework for the development of high-level applications (HLAs) has been created. The key part of the new framework is a dual-layer physical module to facilitate the seamless fusion of physical simulation models with the real machine, allowing for fast switching between different simulation models to accommodate the various simulation scenarios. As a framework designed for development of physical applications, all variables are based on physical quantities. This allows physicists to analytically assess measurement parameters and optimize machine parameters in a more intuitive manner. To enhance both extensibility and adaptability, a modular design strategy is utilized, partitioning the entire framework into discrete modules in alignment with the requirements of HLA development. This strategy not only facilitates the independent development of each module but also minimizes inter-module coupling, thereby simplifying the maintenance and expansion of the entire framework. To simplify the development complexity, the design of the new framework is implemented using Python and is called Python-based Accelerator Physics Application Set (Pyapas). Taking advantage of Python's flexibility and robust library support, we are able to develop and iterate quickly, while also allowing for seamless integration with other scientific computing applications. HLAs for both the HEPS linac and booster have been successfully developed. During the beam commissioning process at the linac, Pyapas's ease of use and reliability have significantly reduced the time required for the beam commissioning operators. As a development framework for HLA designed for the new-generation light sources, Pyapas has the versatility to be employed with HEPS, as well as with other comparable light sources, due to its adaptability.textAs a representative of the fourth-generation light sources, the High Energy Photon Source (HEPS) in Beijing, China, utilizes a multi-bend achromat lattice to obtain an approximately 100 times emittance reduction compared with third-generation light sources. New technologies bring new challenges to operate the storage ring. In order to meet the beam commissioning requirements of HEPS, a new framework for the development of high-level applications (HLAs) has been created. The key part of the new framework is a dual-layer physical module to facilitate the seamless fusion of physical simulation models with the real machine, allowing for fast switching between different simulation models to accommodate the various simulation scenarios. As a framework designed for development of physical applications, all variables are based on physical quantities. This allows physicists to analytically assess measurement parameters and optimize machine parameters in a more intuitive manner. To enhance both extensibility and adaptability, a modular design strategy is utilized, partitioning the entire framework into discrete modules in alignment with the requirements of HLA development. This strategy not only facilitates the independent development of each module but also minimizes inter-module coupling, thereby simplifying the maintenance and expansion of the entire framework. To simplify the development complexity, the design of the new framework is implemented using Python and is called Python-based Accelerator Physics Application Set (Pyapas). Taking advantage of Python's flexibility and robust library support, we are able to develop and iterate quickly, while also allowing for seamless integration with other scientific computing applications. HLAs for both the HEPS linac and booster have been successfully developed. During the beam commissioning process at the linac, Pyapas's ease of use and reliability have significantly reduced the time required for the beam commissioning operators. As a development framework for HLA designed for the new-generation light sources, Pyapas has the versatility to be employed with HEPS, as well as with other comparable light sources, due to its adaptability.urn:issn:1600-5775text/htmlThe development of Pyapas, a new framework for high-level applications at the High Energy Photon Source, Beijing, China, is discussed. Pyapas enables the easy integration of simulation models with real machine operations, simplifies development complexity, and has been shown to effectively reduce time for beam commissioning.2024-02-01HIGH-LEVEL APPLICATION; PYAPAS; PHYSICAL QUANTITIESA new modular framework for high-level application development at HEPSInternational Union of CrystallographyLu, X.Zhao, Y.Ji, H.Jiao, Y.Li, J.Li, N.Meng, C.Peng, Y.Ji, D.Wei, Y.Xu, H.Pan, W.Xu, G.doi:10.1107/S160057752301086Xenhttps://creativecommons.org/licenses/by/4.0/March 202439331Journal of Synchrotron Radiation1600-57752024-02-01med@iucr.org385computer programs2https://creativecommons.org/licenses/by/4.0/1600-5775A thermal deformation optimization method for cryogenically cooled silicon crystal monochromators under high heat load
http://scripts.iucr.org/cgi-bin/paper?tv5046
A method to optimize the thermal deformation of an indirectly cryo-cooled silicon crystal monochromator exposed to intense X-rays at a low-emittance diffraction-limited synchrotron radiation source is presented. The thermal-induced slope error of the monochromator crystal has been studied as a function of heat transfer efficiency, crystal temperature distribution and beam footprint size. A partial cooling method is proposed, which flattens the crystal surface profile within the beam footprint by modifying the cooling contact area to optimize the crystal peak temperature. The optimal temperature varies with different photon energies, which is investigated, and a proper cooling strategy is obtained to fulfil the thermal distortion requirements over the entire photon energy range. At an absorbed power up to 300 W with a maximum power density of 44.8 W mm−2 normal incidence beam from an in-vacuum undulator, the crystal thermal distortion does not exceed 0.3 µrad at 8.33 keV. This method will provide references for the monochromator design on diffraction-limited synchrotron radiation or free-electron laser light sources.textA method to optimize the thermal deformation of an indirectly cryo-cooled silicon crystal monochromator exposed to intense X-rays at a low-emittance diffraction-limited synchrotron radiation source is presented. The thermal-induced slope error of the monochromator crystal has been studied as a function of heat transfer efficiency, crystal temperature distribution and beam footprint size. A partial cooling method is proposed, which flattens the crystal surface profile within the beam footprint by modifying the cooling contact area to optimize the crystal peak temperature. The optimal temperature varies with different photon energies, which is investigated, and a proper cooling strategy is obtained to fulfil the thermal distortion requirements over the entire photon energy range. At an absorbed power up to 300 W with a maximum power density of 44.8 W mm−2 normal incidence beam from an in-vacuum undulator, the crystal thermal distortion does not exceed 0.3 µrad at 8.33 keV. This method will provide references for the monochromator design on diffraction-limited synchrotron radiation or free-electron laser light sources.urn:issn:1600-5775text/htmlA partial cooling method is proposed for minimizing thermal deformation of the monochromator crystal at low-emittance diffraction-limited synchrotron radiation beamlines. The influence of the heat transfer efficiency, crystal temperature distribution and beam size on crystal surface was investigated, and a set of thermal deformation optimization techniques for high-heat-load monochromators was developed.2024-01-22MONOCHROMATOR; SILICON CRYSTAL; THERMAL DEFORMATION; CRYO-COOLED SCHEMEA thermal deformation optimization method for cryogenically cooled silicon crystal monochromators under high heat loadInternational Union of CrystallographyLiu, J.Ji, Z.Fan, Y.Yan, X.Wang, M.Qin, H.doi:10.1107/S1600577523010664enhttps://creativecommons.org/licenses/by/4.0/Journal of Synchrotron Radiation31267March 20242024-01-221600-5775med@iucr.orgresearch papers260https://creativecommons.org/licenses/by/4.0/21600-5775Finback: a web-based data collection system at SSRF biological macromolecular crystallography beamlines
http://scripts.iucr.org/cgi-bin/paper?wz5035
An integrated computer software system for macromolecular crystallography (MX) data collection at the BL02U1 and BL10U2 beamlines of the Shanghai Synchrotron Radiation Facility is described. The system, Finback, implements a set of features designed for the automated MX beamlines, and is marked with a user-friendly web-based graphical user interface (GUI) for interactive data collection. The Finback client GUI can run on modern browsers and has been developed using several modern web technologies including WebSocket, WebGL, WebWorker and WebAssembly. Finback supports multiple concurrent sessions, so on-site and remote users can access the beamline simultaneously. Finback also cooperates with the deployed experimental data and information management system, the relevant experimental parameters and results are automatically deposited to a database.textAn integrated computer software system for macromolecular crystallography (MX) data collection at the BL02U1 and BL10U2 beamlines of the Shanghai Synchrotron Radiation Facility is described. The system, Finback, implements a set of features designed for the automated MX beamlines, and is marked with a user-friendly web-based graphical user interface (GUI) for interactive data collection. The Finback client GUI can run on modern browsers and has been developed using several modern web technologies including WebSocket, WebGL, WebWorker and WebAssembly. Finback supports multiple concurrent sessions, so on-site and remote users can access the beamline simultaneously. Finback also cooperates with the deployed experimental data and information management system, the relevant experimental parameters and results are automatically deposited to a database.urn:issn:1600-5775text/htmlFinback is a biological macromolecular crystallography data collection system that features a user-friendly interactive web-based graphical user interface. The backend is based on the Experimental Physics and Industrial Control System and the frontend has been developed with several modern network technologies including WebSocket, WebGL, WebWorker and WebAssembly.2024-01-19MACROMOLECULAR CRYSTALLOGRAPHY BEAMLINE; DATA COLLECTION; SYNCHROTRON BEAMLINE CONTROL; GRAPHICAL USER INTERFACEFinback: a web-based data collection system at SSRF biological macromolecular crystallography beamlinesInternational Union of CrystallographyYu, F.Liu, K.Zhou, H.Li, M.Kong, H.Zhang, K.Wang, X.Wang, W.Xu, Q.Pan, Q.Wang, Z.Wang, Q.doi:10.1107/S1600577523010615enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752024-01-19March 2024Journal of Synchrotron Radiation311600-57752https://creativecommons.org/licenses/by/4.0/computer programsCorrelation of refractive index based and THz streaking arrival time tools for a hard X-ray free-electron laser
http://scripts.iucr.org/cgi-bin/paper?ve5173
To fully exploit ultra-short X-ray pulse durations routinely available at X-ray free-electron lasers to follow out-of-equilibrium dynamics, inherent arrival time fluctuations of the X-ray pulse with an external perturbing laser pulse need to be measured. In this work, two methods of arrival time measurement were compared to measure the arrival time jitter of hard X-ray pulses. The methods were photoelectron streaking by a THz field and a transient refractive index change of a semiconductor. The methods were validated by shot-to-shot correction of a pump–probe transient reflectivity measurement. An ultimate shot-to-shot full width at half-maximum error between the devices of 19.2 ± 0.1 fs was measured.textTo fully exploit ultra-short X-ray pulse durations routinely available at X-ray free-electron lasers to follow out-of-equilibrium dynamics, inherent arrival time fluctuations of the X-ray pulse with an external perturbing laser pulse need to be measured. In this work, two methods of arrival time measurement were compared to measure the arrival time jitter of hard X-ray pulses. The methods were photoelectron streaking by a THz field and a transient refractive index change of a semiconductor. The methods were validated by shot-to-shot correction of a pump–probe transient reflectivity measurement. An ultimate shot-to-shot full width at half-maximum error between the devices of 19.2 ± 0.1 fs was measured.urn:issn:1600-5775text/htmlThe X-ray free-electron laser pulse arrival time was measured at SwissFEL by THz streaking and spatial encoding simultaneously. The performance of the device was validated by shot-to-shot correction of a pump–probe measurement. The data processing and sources of jitter are discussed.2024-01-22X-RAY FREE-ELECTRON LASERS; TIMING TOOLS; THZ STREAKING; SPATIAL ENCODINGCorrelation of refractive index based and THz streaking arrival time tools for a hard X-ray free-electron laserInternational Union of CrystallographyBłachucki, W.Johnson, P.J.M.Usov, I.Divall, E.Cirelli, C.Knopp, G.Juranić, P.Patthey, L.Szlachetko, J.Lemke, H.Milne, C.Arrell, C.doi:10.1107/S1600577523010500enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/2233research papersmed@iucr.org1600-57752024-01-22March 202431Journal of Synchrotron Radiation242Combination of XEOL, TR-XEOL and HB-T interferometer at the TPS 23A X-ray nanoprobe for exploring quantum materials
http://scripts.iucr.org/cgi-bin/paper?ye5041
In this study, a combination of X-ray excited optical luminescence (XEOL), time-resolved XEOL (TR-XEOL) and the Hanbury-Brown and Twiss (HB-T) interferometer at the Taiwan Photon Source (TPS) 23A X-ray nanoprobe beamline for exploring quantum materials is demonstrated. On the basis of the excellent spatial resolution rendered using a nano-focused beam, emission distributions of artificial micro-diamonds can be obtained by XEOL maps, and featured emission peaks of a selected local area can be obtained by XEOL spectra. The hybrid bunch mode of the TPS not only provides a sufficiently high peak power density for experiments at each beamline but also permits high-quality temporal domain (∼200 ns) measurements for investigating luminescence dynamics. From TR-XEOL measurements, the decay lifetime of micro-diamonds is determined to be approximately 16 ns. Furthermore, the XEOL spectra of artificial micro-diamonds can be investigated by the HB-T interferometer to identify properties of single-photon sources. The unprecedented strategy of combining XEOL, TR-XEOL and the HB-T interferometer at the X-ray nanoprobe beamline will open new avenues with significant characterization abilities for unraveling the emission mechanisms of single-photon sources for quantum materials.textIn this study, a combination of X-ray excited optical luminescence (XEOL), time-resolved XEOL (TR-XEOL) and the Hanbury-Brown and Twiss (HB-T) interferometer at the Taiwan Photon Source (TPS) 23A X-ray nanoprobe beamline for exploring quantum materials is demonstrated. On the basis of the excellent spatial resolution rendered using a nano-focused beam, emission distributions of artificial micro-diamonds can be obtained by XEOL maps, and featured emission peaks of a selected local area can be obtained by XEOL spectra. The hybrid bunch mode of the TPS not only provides a sufficiently high peak power density for experiments at each beamline but also permits high-quality temporal domain (∼200 ns) measurements for investigating luminescence dynamics. From TR-XEOL measurements, the decay lifetime of micro-diamonds is determined to be approximately 16 ns. Furthermore, the XEOL spectra of artificial micro-diamonds can be investigated by the HB-T interferometer to identify properties of single-photon sources. The unprecedented strategy of combining XEOL, TR-XEOL and the HB-T interferometer at the X-ray nanoprobe beamline will open new avenues with significant characterization abilities for unraveling the emission mechanisms of single-photon sources for quantum materials.urn:issn:1600-5775text/htmlThe unprecedented strategy of combining XEOL, TR-XEOL and the HB-T interferometer at the TPS 23A X-ray nanoprobe beamline will open new avenues for exploring quantum materials.2024-01-19X-RAY NANOPROBE; XEOL; TR-XEOL; HB-TCombination of XEOL, TR-XEOL and HB-T interferometer at the TPS 23A X-ray nanoprobe for exploring quantum materialsInternational Union of CrystallographyHuang, T.-C.Ke, S.-W.Wu, Y.-H.Wang, E.-R.Wei, W.-L.Lee, C.-Y.Chen, B.-Y.Yin, G.-C.Chang, H.-W.Tang, M.-T.Lin, B.-H.doi:10.1107/S1600577523010469enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752024-01-19March 202431Journal of Synchrotron Radiation1600-57752https://creativecommons.org/licenses/by/4.0/research papersAngle-resolved X-ray emission spectroscopy facility realized by an innovative spectrometer rotation mechanism at SPring-8 BL07LSU
http://scripts.iucr.org/cgi-bin/paper?iy5001
The X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45–135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities.textThe X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45–135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities.urn:issn:1600-5775text/htmlThe X-ray emission spectrometer at SPring-8 BL07LSU has been upgraded for flexible spectrometer rotation, enabling angle-resolved measurements. This upgrade includes a sophisticated sample chamber, precise rotation mechanism and an integrated control system, streamlining measurements and expanding its usability.2024-02-01X-RAY EMISSION SPECTROSCOPY; RESONANT INELASTIC X-RAY SCATTERING; SPECTROMETERAngle-resolved X-ray emission spectroscopy facility realized by an innovative spectrometer rotation mechanism at SPring-8 BL07LSUInternational Union of CrystallographyMiyawaki, J.Kosegawa, Y.Harada, Y.doi:10.1107/S1600577523010391enhttps://creativecommons.org/licenses/by/4.0/1600-57752https://creativecommons.org/licenses/by/4.0/208research papersmed@iucr.org2024-02-011600-577521631Journal of Synchrotron RadiationMarch 2024In situ characterization of stresses, deformation and fracture of thin films using transmission X-ray nanodiffraction microscopy
http://scripts.iucr.org/cgi-bin/paper?vl5017
The use of hard X-ray transmission nano- and microdiffraction to perform in situ stress and strain measurements during deformation has recently been demonstrated and used to investigate many thin film systems. Here a newly commissioned sample environment based on a commercially available nanoindenter is presented, which is available at the NanoMAX beamline at the MAX IV synchrotron. Using X-ray nanoprobes of around 60–70 nm at 14–16 keV and a scanning step size of 100 nm, we map the strains, stresses, plastic deformation and fracture during nanoindentation of industrial coatings with thicknesses in the range of several micrometres, relatively strong texture and large grains. The successful measurements of such challenging samples illustrate broad applicability. The sample environment is openly accessible for NanoMAX beamline users through the MAX IV sample environment pool, and its capability can be further extended for specific purposes through additional available modules.textThe use of hard X-ray transmission nano- and microdiffraction to perform in situ stress and strain measurements during deformation has recently been demonstrated and used to investigate many thin film systems. Here a newly commissioned sample environment based on a commercially available nanoindenter is presented, which is available at the NanoMAX beamline at the MAX IV synchrotron. Using X-ray nanoprobes of around 60–70 nm at 14–16 keV and a scanning step size of 100 nm, we map the strains, stresses, plastic deformation and fracture during nanoindentation of industrial coatings with thicknesses in the range of several micrometres, relatively strong texture and large grains. The successful measurements of such challenging samples illustrate broad applicability. The sample environment is openly accessible for NanoMAX beamline users through the MAX IV sample environment pool, and its capability can be further extended for specific purposes through additional available modules.urn:issn:1600-5775text/htmlScanning nanodiffraction mapping was used to map stresses, plastic deformation and cracking of hard coatings during nanoindentation.2024-01-01NANODIFFRACTION; STRESS MAPPING; IN SITU DEFORMATION; NANOINDENTATION; SAMPLE ENVIRONMENTIn situ characterization of stresses, deformation and fracture of thin films using transmission X-ray nanodiffraction microscopyInternational Union of CrystallographyLotze, G.Iyer, A.H.S.Bäcke, O.Kalbfleisch, S.Colliander, M.H.doi:10.1107/S1600577523010093enhttps://creativecommons.org/licenses/by/4.0/31Journal of Synchrotron Radiation54January 2024med@iucr.org2024-01-011600-5775https://creativecommons.org/licenses/by/4.0/142research papers1600-5775Heitt Mjölnir: a heated miniature triaxial apparatus for 4D synchrotron microtomography
http://scripts.iucr.org/cgi-bin/paper?vl5015
Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm−1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid–rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication.textThird- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm−1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid–rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication.urn:issn:1600-5775text/htmlHeitt Mjolnir, a heated miniature triaxial apparatus for 4D synchrotron microtomography, is described. This new device combines the capacities of a deformation rig and a thermal reactor with large sample volumes and is suitable for a large range of geo-energy applications.2024-01-01SYNCHROTRON X-RAY MICROTOMOGRAPHY; EXPERIMENTAL GEOSCIENCES; ROCK DEFORMATION; FLUID-ROCK INTERACTIONS; IN SITU EXPERIMENTSHeitt Mjölnir: a heated miniature triaxial apparatus for 4D synchrotron microtomographyInternational Union of CrystallographyFreitas, D.Butler, I.B.Elphick, S.C.Gilgannon, J.Rizzo, R.E.Plümper, O.Wheeler, J.Schlepütz, C.M.Marone, F.Fusseis, F.doi:10.1107/S1600577523009876enhttps://creativecommons.org/licenses/by/4.0/150research papers1https://creativecommons.org/licenses/by/4.0/1600-577516131Journal of Synchrotron RadiationJanuary 20242024-01-011600-5775med@iucr.orgDeep learning to overcome Zernike phase-contrast nanoCT artifacts for automated micro-nano porosity segmentation in bone
http://scripts.iucr.org/cgi-bin/paper?mo5274
Bone material contains a hierarchical network of micro- and nano-cavities and channels, known as the lacuna-canalicular network (LCN), that is thought to play an important role in mechanobiology and turnover. The LCN comprises micrometer-sized lacunae, voids that house osteocytes, and submicrometer-sized canaliculi that connect bone cells. Characterization of this network in three dimensions is crucial for many bone studies. To quantify X-ray Zernike phase-contrast nanotomography data, deep learning is used to isolate and assess porosity in artifact-laden tomographies of zebrafish bones. A technical solution is proposed to overcome the halo and shade-off domains in order to reliably obtain the distribution and morphology of the LCN in the tomographic data. Convolutional neural network (CNN) models are utilized with increasing numbers of images, repeatedly validated by `error loss' and `accuracy' metrics. U-Net and Sensor3D CNN models were trained on data obtained from two different synchrotron Zernike phase-contrast transmission X-ray microscopes, the ANATOMIX beamline at SOLEIL (Paris, France) and the P05 beamline at PETRA III (Hamburg, Germany). The Sensor3D CNN model with a smaller batch size of 32 and a training data size of 70 images showed the best performance (accuracy 0.983 and error loss 0.032). The analysis procedures, validated by comparison with human-identified ground-truth images, correctly identified the voids within the bone matrix. This proposed approach may have further application to classify structures in volumetric images that contain non-linear artifacts that degrade image quality and hinder feature identification.textBone material contains a hierarchical network of micro- and nano-cavities and channels, known as the lacuna-canalicular network (LCN), that is thought to play an important role in mechanobiology and turnover. The LCN comprises micrometer-sized lacunae, voids that house osteocytes, and submicrometer-sized canaliculi that connect bone cells. Characterization of this network in three dimensions is crucial for many bone studies. To quantify X-ray Zernike phase-contrast nanotomography data, deep learning is used to isolate and assess porosity in artifact-laden tomographies of zebrafish bones. A technical solution is proposed to overcome the halo and shade-off domains in order to reliably obtain the distribution and morphology of the LCN in the tomographic data. Convolutional neural network (CNN) models are utilized with increasing numbers of images, repeatedly validated by `error loss' and `accuracy' metrics. U-Net and Sensor3D CNN models were trained on data obtained from two different synchrotron Zernike phase-contrast transmission X-ray microscopes, the ANATOMIX beamline at SOLEIL (Paris, France) and the P05 beamline at PETRA III (Hamburg, Germany). The Sensor3D CNN model with a smaller batch size of 32 and a training data size of 70 images showed the best performance (accuracy 0.983 and error loss 0.032). The analysis procedures, validated by comparison with human-identified ground-truth images, correctly identified the voids within the bone matrix. This proposed approach may have further application to classify structures in volumetric images that contain non-linear artifacts that degrade image quality and hinder feature identification.urn:issn:1600-5775text/htmlA deep-learning processing approach is proposed to assess in three dimensions the micro- and nano-porosity in bone imaged by Zernike nano-computed tomography.2024-01-01ZERNIKE PHASE CONTRAST; X-RAY NANOTOMOGRAPHY; DEEP LEARNING; COMPUTER-AIDED IMAGE SEGMENTATION; LACUNA-CANALICULAR NETWORK; SENSOR3D MODEL; U-NET MODELDeep learning to overcome Zernike phase-contrast nanoCT artifacts for automated micro-nano porosity segmentation in boneInternational Union of CrystallographySilveira, A.Greving, I.Longo, E.Scheel, M.Weitkamp, T.Fleck, C.Shahar, R.Zaslansky, P.doi:10.1107/S1600577523009852enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/1research papers136med@iucr.org1600-57752024-01-01January 202431Journal of Synchrotron Radiation149Protocol using similarity score and improved shrink-wrap algorithm for better convergence of phase-retrieval calculation in X-ray diffraction imaging
http://scripts.iucr.org/cgi-bin/paper?yn5104
In X-ray diffraction imaging (XDI), electron density maps of a targeted particle are reconstructed computationally from the diffraction pattern alone using phase-retrieval (PR) algorithms. However, the PR calculations sometimes fail to yield realistic electron density maps that approximate the structure of the particle. This occurs due to the absence of structure amplitudes at and near the zero-scattering angle and the presence of Poisson noise in weak diffraction patterns. Consequently, the PR calculation becomes a bottleneck for XDI structure analyses. Here, a protocol to efficiently yield realistic maps is proposed. The protocol is based on the empirical observation that realistic maps tend to yield low similarity scores, as suggested in our prior study [Sekiguchi et al. (2017), J. Synchrotron Rad. 24, 1024–1038]. Among independently and concurrently executed PR calculations, the protocol modifies all maps using the electron-density maps exhibiting low similarity scores. This approach, along with a new protocol for estimating particle shape, improved the probability of obtaining realistic maps for diffraction patterns from various aggregates of colloidal gold particles, as compared with PR calculations performed without the protocol. Consequently, the protocol has the potential to reduce computational costs in PR calculations and enable efficient XDI structure analysis of non-crystalline particles using synchrotron X-rays and X-ray free-electron laser pulses.textIn X-ray diffraction imaging (XDI), electron density maps of a targeted particle are reconstructed computationally from the diffraction pattern alone using phase-retrieval (PR) algorithms. However, the PR calculations sometimes fail to yield realistic electron density maps that approximate the structure of the particle. This occurs due to the absence of structure amplitudes at and near the zero-scattering angle and the presence of Poisson noise in weak diffraction patterns. Consequently, the PR calculation becomes a bottleneck for XDI structure analyses. Here, a protocol to efficiently yield realistic maps is proposed. The protocol is based on the empirical observation that realistic maps tend to yield low similarity scores, as suggested in our prior study [Sekiguchi et al. (2017), J. Synchrotron Rad. 24, 1024–1038]. Among independently and concurrently executed PR calculations, the protocol modifies all maps using the electron-density maps exhibiting low similarity scores. This approach, along with a new protocol for estimating particle shape, improved the probability of obtaining realistic maps for diffraction patterns from various aggregates of colloidal gold particles, as compared with PR calculations performed without the protocol. Consequently, the protocol has the potential to reduce computational costs in PR calculations and enable efficient XDI structure analysis of non-crystalline particles using synchrotron X-rays and X-ray free-electron laser pulses.urn:issn:1600-5775text/htmlA protocol to steer phase-retrieval calculations to realistic density maps is proposed.2024-01-01X-RAY DIFFRACTION IMAGING; PHASE-RETRIEVAL CALCULATION; STRUCTURE ANALYSIS OF NON-CRYSTALLINE PARTICLES; X-RAY FREE-ELECTRON LASERProtocol using similarity score and improved shrink-wrap algorithm for better convergence of phase-retrieval calculation in X-ray diffraction imagingInternational Union of CrystallographyYoshida, S.Harada, K.Uezu, S.Takayama, Y.Nakasako, M.doi:10.1107/S1600577523009864enhttps://creativecommons.org/licenses/by/4.0/128Journal of Synchrotron Radiation31January 2024med@iucr.org2024-01-011600-57751https://creativecommons.org/licenses/by/4.0/research papers1131600-5775Similarity score for screening phase-retrieved maps in X-ray diffraction imaging – characterization in reciprocal space
http://scripts.iucr.org/cgi-bin/paper?yn5103
X-ray diffraction imaging (XDI) is utilized for visualizing the structures of non-crystalline particles in material sciences and biology. In the structural analysis, phase-retrieval (PR) algorithms are applied to the diffraction amplitude data alone to reconstruct the electron density map of a specimen particle projected along the direction of the incident X-rays. However, PR calculations may not lead to good convergence because of a lack of diffraction patterns in small-angle regions and Poisson noise in X-ray detection. Therefore, the PR calculation is still a bottleneck for the efficient application of XDI in the structural analyses of non-crystalline particles. For screening maps from hundreds of trial PR calculations, we have been using a score and measuring the similarity between a pair of retrieved maps. Empirically, probable maps approximating the particle structures gave a score smaller than a threshold value, but the reasons for the effectiveness of the score are still unclear. In this study, the score is characterized in terms of the phase differences between the structure factors of the retrieved maps, the usefulness of the score in screening the maps retrieved from experimental diffraction patterns is demonstrated, and the effective resolution of similarity-score-selected maps is discussed.textX-ray diffraction imaging (XDI) is utilized for visualizing the structures of non-crystalline particles in material sciences and biology. In the structural analysis, phase-retrieval (PR) algorithms are applied to the diffraction amplitude data alone to reconstruct the electron density map of a specimen particle projected along the direction of the incident X-rays. However, PR calculations may not lead to good convergence because of a lack of diffraction patterns in small-angle regions and Poisson noise in X-ray detection. Therefore, the PR calculation is still a bottleneck for the efficient application of XDI in the structural analyses of non-crystalline particles. For screening maps from hundreds of trial PR calculations, we have been using a score and measuring the similarity between a pair of retrieved maps. Empirically, probable maps approximating the particle structures gave a score smaller than a threshold value, but the reasons for the effectiveness of the score are still unclear. In this study, the score is characterized in terms of the phase differences between the structure factors of the retrieved maps, the usefulness of the score in screening the maps retrieved from experimental diffraction patterns is demonstrated, and the effective resolution of similarity-score-selected maps is discussed.urn:issn:1600-5775text/htmlThe similarity score is a useful metric for screening electron density maps from phase-retrieval calculations in X-ray diffraction imaging. The characteristics of the score have been studied in reciprocal space and are described here.2024-01-01X-RAY DIFFRACTION IMAGING; PHASE RETRIEVAL CALCULATION; PHASE PROBLEMSimilarity score for screening phase-retrieved maps in X-ray diffraction imaging – characterization in reciprocal spaceInternational Union of CrystallographyTakayama, Y.Nakasako, M.doi:10.1107/S1600577523009827enhttps://creativecommons.org/licenses/by/4.0/January 202431Journal of Synchrotron Radiation1121600-57752024-01-01med@iucr.org95research papershttps://creativecommons.org/licenses/by/4.0/11600-5775Performance of a photoelectron momentum microscope in direct- and momentum-space imaging with ultraviolet photon sources
http://scripts.iucr.org/cgi-bin/paper?ok5104
The Photoelectron-Related Image and Nano-Spectroscopy (PRINS) endstation located at the Taiwan Photon Source beamline 27A2 houses a photoelectron momentum microscope capable of performing direct-space imaging, momentum-space imaging and photoemission spectroscopy with position sensitivity. Here, the performance of this microscope is demonstrated using two in-house photon sources – an Hg lamp and He(I) radiation – on a standard checkerboard-patterned specimen and an Au(111) single crystal, respectively. By analyzing the intensity profile of the edge of the Au patterns, the Rashba-splitting of the Au(111) Shockley surface state at 300 K, and the photoelectron intensity across the Fermi edge at 80 K, the spatial, momentum and energy resolution were estimated to be 50 nm, 0.0172 Å−1 and 26 meV, respectively. Additionally, it is shown that the band structures acquired in either constant energy contour mode or momentum-resolved photoemission spectroscopy mode were in close agreement.textThe Photoelectron-Related Image and Nano-Spectroscopy (PRINS) endstation located at the Taiwan Photon Source beamline 27A2 houses a photoelectron momentum microscope capable of performing direct-space imaging, momentum-space imaging and photoemission spectroscopy with position sensitivity. Here, the performance of this microscope is demonstrated using two in-house photon sources – an Hg lamp and He(I) radiation – on a standard checkerboard-patterned specimen and an Au(111) single crystal, respectively. By analyzing the intensity profile of the edge of the Au patterns, the Rashba-splitting of the Au(111) Shockley surface state at 300 K, and the photoelectron intensity across the Fermi edge at 80 K, the spatial, momentum and energy resolution were estimated to be 50 nm, 0.0172 Å−1 and 26 meV, respectively. Additionally, it is shown that the band structures acquired in either constant energy contour mode or momentum-resolved photoemission spectroscopy mode were in close agreement.urn:issn:1600-5775text/htmlA microscope hosted at Taiwan Photon Source beamline 27A2 that packs the functions of photoemission electron microscopy and angle-resolved photoemission spectroscopy into one single instrument is presented.2024-01-01MOMENTUM MICROSCOPE; PHOTOEMISSION; ELECTRONIC STRUCTURE; FERMI CONTOUR; RASHBA-SPLITTINGPerformance of a photoelectron momentum microscope in direct- and momentum-space imaging with ultraviolet photon sourcesInternational Union of CrystallographyChuang, T.-H.Hsu, C.-C.Chiu, W.-S.Jhuang, J.-S.Yeh, I.-C.Chen, R.-S.Gwo, S.Wei, D.-H.doi:10.1107/S1600577523009761enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org2024-01-011600-5775201Journal of Synchrotron Radiation31January 20241600-57751https://creativecommons.org/licenses/by/4.0/195beamlinesTreatment of multiple-beam X-ray diffraction in energy-dependent measurements
http://scripts.iucr.org/cgi-bin/paper?fv5164
During X-ray diffraction experiments on single crystals, the diffracted beam intensities may be affected by multiple-beam X-ray diffraction (MBD). This effect is particularly frequent at higher X-ray energies and for larger unit cells. The appearance of this so-called Renninger effect often impairs the interpretation of diffracted intensities. This applies in particular to energy spectra analysed in resonant experiments, since during scans of the incident photon energy these conditions are necessarily met for specific X-ray energies. This effect can be addressed by carefully avoiding multiple-beam reflection conditions at a given X-ray energy and a given position in reciprocal space. However, areas which are (nearly) free of MBD are not always available. This article presents a universal concept of data acquisition and post-processing for resonant X-ray diffraction experiments. Our concept facilitates the reliable determination of kinematic (MBD-free) resonant diffraction intensities even at relatively high energies which, in turn, enables the study of higher absorption edges. This way, the applicability of resonant diffraction, e.g. to reveal the local atomic and electronic structure or chemical environment, is extended for a vast majority of crystalline materials. The potential of this approach compared with conventional data reduction is demonstrated by the measurements of the Ta L3 edge of well studied lithium tantalate LiTaO3.textDuring X-ray diffraction experiments on single crystals, the diffracted beam intensities may be affected by multiple-beam X-ray diffraction (MBD). This effect is particularly frequent at higher X-ray energies and for larger unit cells. The appearance of this so-called Renninger effect often impairs the interpretation of diffracted intensities. This applies in particular to energy spectra analysed in resonant experiments, since during scans of the incident photon energy these conditions are necessarily met for specific X-ray energies. This effect can be addressed by carefully avoiding multiple-beam reflection conditions at a given X-ray energy and a given position in reciprocal space. However, areas which are (nearly) free of MBD are not always available. This article presents a universal concept of data acquisition and post-processing for resonant X-ray diffraction experiments. Our concept facilitates the reliable determination of kinematic (MBD-free) resonant diffraction intensities even at relatively high energies which, in turn, enables the study of higher absorption edges. This way, the applicability of resonant diffraction, e.g. to reveal the local atomic and electronic structure or chemical environment, is extended for a vast majority of crystalline materials. The potential of this approach compared with conventional data reduction is demonstrated by the measurements of the Ta L3 edge of well studied lithium tantalate LiTaO3.urn:issn:1600-5775text/htmlAn approach to reliably extract the desired intensities and filter out multiple-beam X-ray diffraction, which often causes interference for high X-ray energies and for large unit cells, is presented. Here, a universal concept of data acquisition and post-processing for resonant X-ray diffraction experiments is described, including the measurement of the energy-dependent intensity at several azimuth angles and subsequently only considering the unaffected data points.2024-01-01RESONANT ELASTIC X-RAY SCATTERING; MULTIPLE-BEAM X-RAY DIFFRACTION; RENNINGER EFFECT; DATA PROCESSINGTreatment of multiple-beam X-ray diffraction in energy-dependent measurementsInternational Union of CrystallographyNentwich, M.Zschornak, M.Weigel, T.Köhler, T.Novikov, D.Meyer, D.C.Richter, C.doi:10.1107/S1600577523009670enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/128research papers1600-5775January 202431Journal of Synchrotron Radiation34med@iucr.org1600-57752024-01-01Efficient boundary-guided scanning for high-resolution X-ray ptychography
http://scripts.iucr.org/cgi-bin/paper?gy5051
In the realm of X-ray ptychography experiments, a considerable amount of ptychography scans are typically performed within a field of view encompassing the target sample. While it is crucial to obtain overlapping scans in small increments over the region of interest for achieving high-resolution sample reconstruction, a significant number of these scans often redundantly measure the empty background within the wide field of view. To address this inefficiency, an innovative algorithm is proposed that introduces automatic guidance for data acquisition. The algorithm first directs the scan point to actively search for the object of interest within the field of view. Subsequently, it intelligently scans along the perimeter of the sample, strategically acquiring measurements exclusively within the boundary of the region of interest. By employing this approach, a reduction in the number of measurements required to obtain high-resolution reconstruction images is demonstrated, as compared with conventional raster scanning methods. Furthermore, the automatic guidance provided by the algorithm offers the added advantage of saving valuable time during the reconstruction process. Through practical implementation on real experiments, these findings showcase the efficacy of the proposed algorithm in enhancing the efficiency and accuracy of X-ray ptychography experiments. This novel approach holds immense potential for advancing sample analysis and imaging techniques in various scientific disciplines.textIn the realm of X-ray ptychography experiments, a considerable amount of ptychography scans are typically performed within a field of view encompassing the target sample. While it is crucial to obtain overlapping scans in small increments over the region of interest for achieving high-resolution sample reconstruction, a significant number of these scans often redundantly measure the empty background within the wide field of view. To address this inefficiency, an innovative algorithm is proposed that introduces automatic guidance for data acquisition. The algorithm first directs the scan point to actively search for the object of interest within the field of view. Subsequently, it intelligently scans along the perimeter of the sample, strategically acquiring measurements exclusively within the boundary of the region of interest. By employing this approach, a reduction in the number of measurements required to obtain high-resolution reconstruction images is demonstrated, as compared with conventional raster scanning methods. Furthermore, the automatic guidance provided by the algorithm offers the added advantage of saving valuable time during the reconstruction process. Through practical implementation on real experiments, these findings showcase the efficacy of the proposed algorithm in enhancing the efficiency and accuracy of X-ray ptychography experiments. This novel approach holds immense potential for advancing sample analysis and imaging techniques in various scientific disciplines.urn:issn:1600-5775text/htmlAn innovative adaptive scan technique for high-resolution X-ray ptychography is introduced that offers automated guidance for the scan trajectory along an object's boundary, selectively acquiring measurements relevant to the region of interest.2024-01-01X-RAY PTYCHOGRAPHY; AUTOMATED DATA ACQUISITIONEfficient boundary-guided scanning for high-resolution X-ray ptychographyInternational Union of CrystallographyLin, D.Jiang, Y.Deng, J.Marin, F.S.Di, Z.W.doi:10.1107/S1600577523009657enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/1research papers129med@iucr.org2024-01-011600-577531Journal of Synchrotron Radiation135January 2024The African Light Source: history, context and future
http://scripts.iucr.org/cgi-bin/paper?ok5102
The African Light Source (AfLS) project is now almost eight years old. This article assesses the history, current context and future of the project. There is by now considerable momentum in building the user community, including deep training, facilitating access to current facilities, growing the scientific output, scientific networks and growing the local laboratory-scale research infrastructure. The Conceptual Design Report for the AfLS is in its final editing stages. This document specifies the socio-economic and scientific rationales and the technical aspects amongst others. The AfLS is supported by many national and Pan-African scientific professional bodies and voluntary associates across many scientific disciplines, and there are stakeholders throughout the continent and beyond. The current roadmap phases have expanded to include national and Pan-African level conversations with policy makers through new Strategic Task Force groups. The document summarizes this progress and discusses the future of the project.textThe African Light Source (AfLS) project is now almost eight years old. This article assesses the history, current context and future of the project. There is by now considerable momentum in building the user community, including deep training, facilitating access to current facilities, growing the scientific output, scientific networks and growing the local laboratory-scale research infrastructure. The Conceptual Design Report for the AfLS is in its final editing stages. This document specifies the socio-economic and scientific rationales and the technical aspects amongst others. The AfLS is supported by many national and Pan-African scientific professional bodies and voluntary associates across many scientific disciplines, and there are stakeholders throughout the continent and beyond. The current roadmap phases have expanded to include national and Pan-African level conversations with policy makers through new Strategic Task Force groups. The document summarizes this progress and discusses the future of the project.urn:issn:1600-5775text/htmlThe African Light Source project towards a light source for the African continent is described.2024-01-01AFRICAN LIGHT SOURCE; AFLS; SYNCHROTRON; HISTORYThe African Light Source: history, context and futureInternational Union of CrystallographyConnell, S.H.Dollman, K.Kamel, G.Khan, S.A.Mitchell, E.Mtingwa, S.K.Newton, M.C.Ngabonziza, P.Nji, E.Norris, L.Zema, M.doi:10.1107/S1600577523009682enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/1feature articles11600-5775January 202431Journal of Synchrotron Radiation9med@iucr.org1600-57752024-01-01A method with ultra-high angular resolution for X-ray diffraction experiments
http://scripts.iucr.org/cgi-bin/paper?gy5052
In X-ray diffraction measurements, the angular resolution has a detection limit due to the receiving size of the detector. In many cases this detection limit is too large and must be breached to obtain the desired information. A novel method is proposed here by making the detector simultaneously measuring and moving. Using the deconvolution algorithm to remove the convolution effect, the pixel size limitation is finally broken. The algorithm used is not a common one, and suppresses signals at high frequencies, ensuring the reliability of the peak shape after restoration. The feasibility of this method is verified by successfully measuring the crystal truncation rod signal of SrTiO3 single crystal, and the resolution is nearly ten times higher than that of a single pixel. Moreover, this method greatly reduces the noise and improves the signal-to-noise ratio.textIn X-ray diffraction measurements, the angular resolution has a detection limit due to the receiving size of the detector. In many cases this detection limit is too large and must be breached to obtain the desired information. A novel method is proposed here by making the detector simultaneously measuring and moving. Using the deconvolution algorithm to remove the convolution effect, the pixel size limitation is finally broken. The algorithm used is not a common one, and suppresses signals at high frequencies, ensuring the reliability of the peak shape after restoration. The feasibility of this method is verified by successfully measuring the crystal truncation rod signal of SrTiO3 single crystal, and the resolution is nearly ten times higher than that of a single pixel. Moreover, this method greatly reduces the noise and improves the signal-to-noise ratio.urn:issn:1600-5775text/htmlA method to acquire X-ray scattered signals at high frequency while the detector is moving is proposed. The algorithm provided can break through the pixel size limitation, and the resolution is improved by almost ten times compared with that of a single pixel.2024-01-01DECONVOLUTION; SUPER RESOLUTION; X-RAY DIFFRACTION; CRYSTAL TRUNCATION RODA method with ultra-high angular resolution for X-ray diffraction experimentsInternational Union of CrystallographyZhang, X.M.Zheng, X.Li, X.L.Meng, F.Q.Yin, S.S.doi:10.1107/S160057752300961Xenhttps://creativecommons.org/licenses/by/4.0/research papers35https://creativecommons.org/licenses/by/4.0/11600-5775January 202431Journal of Synchrotron Radiation411600-57752024-01-01med@iucr.orgAn active piezoelectric plane X-ray focusing mirror with a linearly changing thickness
http://scripts.iucr.org/cgi-bin/paper?tv5050
X-ray mirrors for synchrotron radiation are often bent into a curved figure and work under grazing-incidence conditions due to the strong penetrating nature of X-rays to most materials. Mirrors of different cross sections have been recommended to reduce the mirror's slope inaccuracy and clamping difficulty in order to overcome mechanical tolerances. With the development of hard X-ray focusing, it is difficult to meet the needs of focusing mirrors with small slope error with the existing mirror processing technology. Deformable mirrors are adaptive optics that can produce a flexible surface figure. A method of using a deformable mirror as a phase compensator is described to enhance the focusing performance of an X-ray mirror. This paper presents an active piezoelectric plane X-ray focusing mirror with a linearly changing thickness that has the ability of phase compensation while focusing X-rays. Benefiting from its special structural design, the mirror can realize flexible focusing at different focusing geometries using a single input driving voltage. A prototype was used to measure its performance under one-dimension and two-dimension conditions. The results prove that, even at a bending magnet beamline, the mirror can easily achieve a single-micrometre focusing without a complicated bending mechanism or high-precision surface processing. It is hoped that this kind of deformable mirror will have a wide and flexible application in the synchrotron radiation field.textX-ray mirrors for synchrotron radiation are often bent into a curved figure and work under grazing-incidence conditions due to the strong penetrating nature of X-rays to most materials. Mirrors of different cross sections have been recommended to reduce the mirror's slope inaccuracy and clamping difficulty in order to overcome mechanical tolerances. With the development of hard X-ray focusing, it is difficult to meet the needs of focusing mirrors with small slope error with the existing mirror processing technology. Deformable mirrors are adaptive optics that can produce a flexible surface figure. A method of using a deformable mirror as a phase compensator is described to enhance the focusing performance of an X-ray mirror. This paper presents an active piezoelectric plane X-ray focusing mirror with a linearly changing thickness that has the ability of phase compensation while focusing X-rays. Benefiting from its special structural design, the mirror can realize flexible focusing at different focusing geometries using a single input driving voltage. A prototype was used to measure its performance under one-dimension and two-dimension conditions. The results prove that, even at a bending magnet beamline, the mirror can easily achieve a single-micrometre focusing without a complicated bending mechanism or high-precision surface processing. It is hoped that this kind of deformable mirror will have a wide and flexible application in the synchrotron radiation field.urn:issn:1600-5775text/htmlAn active piezoelectric plane X-ray focusing mirror with a linearly changing thickness is presented. Focusing performances of the prototype are measured and a single-micrometre focusing result is achieved.2024-01-01SYNCHROTRON RADIATION; PIEZOELECTRIC DEFORMABLE MIRROR; X-RAY FOCUSING; SPECKLE METROLOGYAn active piezoelectric plane X-ray focusing mirror with a linearly changing thicknessInternational Union of CrystallographyTian, N.Jiang, H.Xie, J.Yan, S.Liang, D.Jiang, Z.doi:10.1107/S1600577523009566enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/1research papers101600-5775Journal of Synchrotron Radiation3116January 2024med@iucr.org2024-01-011600-5775In situ/operando plug-flow fixed-bed cell for synchrotron PXRD and XAFS investigations at high temperature, pressure, controlled gas atmosphere and ultra-fast heating
http://scripts.iucr.org/cgi-bin/paper?vl5016
A plug-flow fixed-bed cell for synchrotron powder X-ray diffraction (PXRD) and X-ray absorption fine structure (XAFS) idoneous for the study of heterogeneous catalysts at high temperature, pressure and under gas flow is designed, constructed and demonstrated. The operating conditions up to 1000°C and 50 bar are ensured by a set of mass flow controllers, pressure regulators and two infra-red lamps that constitute a robust and ultra-fast heating and cooling method. The performance of the system and cell for carbon dioxide hydrogenation reactions under specified temperatures, gas flows and pressures is demonstrated both for PXRD and XAFS at the P02.1 (PXRD) and the P64 (XAFS) beamlines of the Deutsches Elektronen-Synchrotron (DESY).textA plug-flow fixed-bed cell for synchrotron powder X-ray diffraction (PXRD) and X-ray absorption fine structure (XAFS) idoneous for the study of heterogeneous catalysts at high temperature, pressure and under gas flow is designed, constructed and demonstrated. The operating conditions up to 1000°C and 50 bar are ensured by a set of mass flow controllers, pressure regulators and two infra-red lamps that constitute a robust and ultra-fast heating and cooling method. The performance of the system and cell for carbon dioxide hydrogenation reactions under specified temperatures, gas flows and pressures is demonstrated both for PXRD and XAFS at the P02.1 (PXRD) and the P64 (XAFS) beamlines of the Deutsches Elektronen-Synchrotron (DESY).urn:issn:1600-5775text/htmlA plug-flow fixed-bed cell for synchrotron powder X-ray diffraction (PXRD) and X-ray absorption fine-structure (XAFS) idoneous for the study of heterogeneous catalysts at high temperature, pressure and under gas flow is designed, constructed and demonstrated. The operating conditions up to 1000°C and 50 bar are ensured by a set of mass flow controllers, pressure regulators and two infra-red lamps that constitute a robust and ultra-fast heating and cooling method.2024-01-01PLUG-FLOW FIXED-BED CELL; ULTRA-FAST INFRA-RED HEATING; GAS-SOLID INTERACTIONS; IN SITU X-RAY DIFFRACTION; IN SITU X-RAY ABSORPTION FINE STRUCTUREIn situ/operando plug-flow fixed-bed cell for synchrotron PXRD and XAFS investigations at high temperature, pressure, controlled gas atmosphere and ultra-fast heatingInternational Union of CrystallographyBischoff, B.Bekheet, M.F.Dal Molin, E.Praetz, S.Kanngießer, B.Schomäcker, R.Etter, M.Jeppesen, H.S.Tayal, A.Gurlo, A.Gili, A.doi:10.1107/S1600577523009591enhttps://creativecommons.org/licenses/by/4.0/8431Journal of Synchrotron RadiationJanuary 20242024-01-011600-5775med@iucr.orgresearch papers771https://creativecommons.org/licenses/by/4.0/1600-5775High Throughput Tomography (HiTT) on EMBL beamline P14 on PETRA III
http://scripts.iucr.org/cgi-bin/paper?ay5623
Here, high-throughput tomography (HiTT), a fast and versatile phase-contrast imaging platform for life-science samples on the EMBL beamline P14 at DESY in Hamburg, Germany, is presented. A high-photon-flux undulator beamline is used to perform tomographic phase-contrast acquisition in about two minutes which is linked to an automated data processing pipeline that delivers a 3D reconstructed data set less than a minute and a half after the completion of the X-ray scan. Combining this workflow with a sophisticated robotic sample changer enables the streamlined collection and reconstruction of X-ray imaging data from potentially hundreds of samples during a beam-time shift. HiTT permits optimal data collection for many different samples and makes possible the imaging of large sample cohorts thus allowing population studies to be attempted. The successful application of HiTT on various soft tissue samples in both liquid (hydrated and also dehydrated) and paraffin-embedded preparations is demonstrated. Furthermore, the feasibility of HiTT to be used as a targeting tool for volume electron microscopy, as well as using HiTT to study plant morphology, is demonstrated. It is also shown how the high-throughput nature of the work has allowed large numbers of `identical' samples to be imaged to enable statistically relevant sample volumes to be studied.textHere, high-throughput tomography (HiTT), a fast and versatile phase-contrast imaging platform for life-science samples on the EMBL beamline P14 at DESY in Hamburg, Germany, is presented. A high-photon-flux undulator beamline is used to perform tomographic phase-contrast acquisition in about two minutes which is linked to an automated data processing pipeline that delivers a 3D reconstructed data set less than a minute and a half after the completion of the X-ray scan. Combining this workflow with a sophisticated robotic sample changer enables the streamlined collection and reconstruction of X-ray imaging data from potentially hundreds of samples during a beam-time shift. HiTT permits optimal data collection for many different samples and makes possible the imaging of large sample cohorts thus allowing population studies to be attempted. The successful application of HiTT on various soft tissue samples in both liquid (hydrated and also dehydrated) and paraffin-embedded preparations is demonstrated. Furthermore, the feasibility of HiTT to be used as a targeting tool for volume electron microscopy, as well as using HiTT to study plant morphology, is demonstrated. It is also shown how the high-throughput nature of the work has allowed large numbers of `identical' samples to be imaged to enable statistically relevant sample volumes to be studied.urn:issn:1600-5775text/htmlHigh-throughput tomography, a propagation-based phase-contrast X-ray imaging technique that can visualize 1 mm3 biological samples of various types at high resolution, is presented. 3D reconstructions of the imaged volumes are calculated automatically once data collection is complete. The entire process from pressing start on data collection to viewing the final data takes less than three minutes. This speed, in combination with the use of an automated sample changer to exchange the samples, truly enables high-throughput X-ray imaging for the first time.2024-01-01X-RAY TOMOGRAPHY; PHASE-CONTRAST IMAGING; BEAMLINES; BIOLOGYHigh Throughput Tomography (HiTT) on EMBL beamline P14 on PETRA IIIInternational Union of CrystallographyAlbers, J.Nikolova, M.Svetlove, A.Darif, N.Lawson, M.J.Schneider, T.R.Schwab, Y.Bourenkov, G.Duke, E.doi:10.1107/S160057752300944Xenhttps://creativecommons.org/licenses/by/4.0/Journal of Synchrotron Radiation31194January 20242024-01-011600-5775med@iucr.orgbeamlines186https://creativecommons.org/licenses/by/4.0/11600-5775Design and first-round commissioning result of the SASE beamline at the Shanghai Soft X-ray FEL facility
http://scripts.iucr.org/cgi-bin/paper?vy5017
The Shanghai Soft X-ray Free-Electron Laser (SXFEL) is the first X-ray free-electron laser facility in China. The SASE beamline, which consists of a pink-beam branch and a mono-beam branch, is one of the two beamlines in the Phase-I construction. The pink-beam branch opened for users in 2023 after successful first-round beamline commissioning. In this paper, the design of the beamline is presented and the performance of the pink-beam branch is reported. The measured energy-resolving power of the online spectrometer is over 6000 @ 400 eV. The focusing spot size of the pink beam is less than 3 µm in both the horizontal and vertical at the endstation.textThe Shanghai Soft X-ray Free-Electron Laser (SXFEL) is the first X-ray free-electron laser facility in China. The SASE beamline, which consists of a pink-beam branch and a mono-beam branch, is one of the two beamlines in the Phase-I construction. The pink-beam branch opened for users in 2023 after successful first-round beamline commissioning. In this paper, the design of the beamline is presented and the performance of the pink-beam branch is reported. The measured energy-resolving power of the online spectrometer is over 6000 @ 400 eV. The focusing spot size of the pink beam is less than 3 µm in both the horizontal and vertical at the endstation.urn:issn:1600-5775text/htmlThe design and first-round commissioning results of the SASE beamline at the Shanghai Soft X-ray FEL facility are presented.2024-01-01FREE-ELECTRON LASER; SASE BEAMLINE; ONLINE SPECTROMETER; FOCUSING SPOTDesign and first-round commissioning result of the SASE beamline at the Shanghai Soft X-ray FEL facilityInternational Union of CrystallographyXue, C.Guo, Z.Liu, H.Chen, J.Tong, Y.Fan, J.Jiang, H.Liu, Z.Zhang, X.Tai, R.doi:10.1107/S1600577523009438enhttps://creativecommons.org/licenses/by/4.0/beamlines1771https://creativecommons.org/licenses/by/4.0/1600-577518531Journal of Synchrotron RadiationJanuary 20242024-01-011600-5775med@iucr.orgX-ray-induced piezoresponse during X-ray photon correlation spectroscopy of PbMg1/3Nb2/3O3
http://scripts.iucr.org/cgi-bin/paper?vl5014
X-ray photon correlation spectroscopy (XPCS) holds strong promise for observing atomic-scale dynamics in materials, both at equilibrium and during non-equilibrium transitions. Here an in situ XPCS study of the relaxor ferroelectric PbMg1/3Nb2/3O3 (PMN) is reported. A weak applied AC electric field generates strong response in the speckle of the diffuse scattering from the polar nanodomains, which is captured using the two-time correlation function. Correlated motions of the Bragg peak are also observed, which indicate dynamic tilting of the illuminated volume. This tilting quantitatively accounts for the observed two-time speckle correlations. The magnitude of the tilting would not be expected solely from the modest applied field, since PMN is an electrostrictive material with no linear strain response to the field. A model is developed based on non-uniform static charging of the illuminated surface spot by the incident micrometre-scale X-ray beam and the electrostrictive material response to the combination of static and dynamic fields. The model qualitatively explains the direction and magnitude of the observed tilting, and predicts that X-ray-induced piezoresponse could be an important factor in correctly interpreting results from XPCS and nanodiffraction studies of other insulating materials under applied AC field or varying X-ray illumination.textX-ray photon correlation spectroscopy (XPCS) holds strong promise for observing atomic-scale dynamics in materials, both at equilibrium and during non-equilibrium transitions. Here an in situ XPCS study of the relaxor ferroelectric PbMg1/3Nb2/3O3 (PMN) is reported. A weak applied AC electric field generates strong response in the speckle of the diffuse scattering from the polar nanodomains, which is captured using the two-time correlation function. Correlated motions of the Bragg peak are also observed, which indicate dynamic tilting of the illuminated volume. This tilting quantitatively accounts for the observed two-time speckle correlations. The magnitude of the tilting would not be expected solely from the modest applied field, since PMN is an electrostrictive material with no linear strain response to the field. A model is developed based on non-uniform static charging of the illuminated surface spot by the incident micrometre-scale X-ray beam and the electrostrictive material response to the combination of static and dynamic fields. The model qualitatively explains the direction and magnitude of the observed tilting, and predicts that X-ray-induced piezoresponse could be an important factor in correctly interpreting results from XPCS and nanodiffraction studies of other insulating materials under applied AC field or varying X-ray illumination.urn:issn:1600-5775text/htmlX-ray illumination induces surface charging and gives rise to substantially enhanced piezoresponse in a relaxor ferroelectric captured by X-ray photon correlation spectroscopy.2024-01-01X-RAY PHOTON CORRELATION SPECTROSCOPY; RELAXOR; SURFACE CHARGING; X-RAY-INDUCED PIEZORESPONSEX-ray-induced piezoresponse during X-ray photon correlation spectroscopy of PbMg1/3Nb2/3O3International Union of CrystallographySheyfer, D.Zheng, H.Krogstad, M.Thompson, C.You, H.Eastman, J.A.Liu, Y.Wang, B.-X.Ye, Z.-G.Rosenkranz, S.Phelan, D.Dufresne, E.M.Stephenson, G.B.Cao, Y.doi:10.1107/S1600577523009116enhttps://creativecommons.org/licenses/by/4.0/January 2024Journal of Synchrotron Radiation311600-57752024-01-01med@iucr.orgresearch papershttps://creativecommons.org/licenses/by/4.0/11600-5775tomoCAM: fast model-based iterative reconstruction via GPU acceleration and non-uniform fast Fourier transforms
http://scripts.iucr.org/cgi-bin/paper?mo5270
X-ray-based computed tomography is a well established technique for determining the three-dimensional structure of an object from its two-dimensional projections. In the past few decades, there have been significant advancements in the brightness and detector technology of tomography instruments at synchrotron sources. These advancements have led to the emergence of new observations and discoveries, with improved capabilities such as faster frame rates, larger fields of view, higher resolution and higher dimensionality. These advancements have enabled the material science community to expand the scope of tomographic measurements towards increasingly in situ and in operando measurements. In these new experiments, samples can be rapidly evolving, have complex geometries and restrictions on the field of view, limiting the number of projections that can be collected. In such cases, standard filtered back-projection often results in poor quality reconstructions. Iterative reconstruction algorithms, such as model-based iterative reconstructions (MBIR), have demonstrated considerable success in producing high-quality reconstructions under such restrictions, but typically require high-performance computing resources with hundreds of compute nodes to solve the problem in a reasonable time. Here, tomoCAM, is introduced, a new GPU-accelerated implementation of model-based iterative reconstruction that leverages non-uniform fast Fourier transforms to efficiently compute Radon and back-projection operators and asynchronous memory transfers to maximize the throughput to the GPU memory. The resulting code is significantly faster than traditional MBIR codes and delivers the reconstructive improvement offered by MBIR with affordable computing time and resources. tomoCAM has a Python front-end, allowing access from Jupyter-based frameworks, providing straightforward integration into existing workflows at synchrotron facilities.textX-ray-based computed tomography is a well established technique for determining the three-dimensional structure of an object from its two-dimensional projections. In the past few decades, there have been significant advancements in the brightness and detector technology of tomography instruments at synchrotron sources. These advancements have led to the emergence of new observations and discoveries, with improved capabilities such as faster frame rates, larger fields of view, higher resolution and higher dimensionality. These advancements have enabled the material science community to expand the scope of tomographic measurements towards increasingly in situ and in operando measurements. In these new experiments, samples can be rapidly evolving, have complex geometries and restrictions on the field of view, limiting the number of projections that can be collected. In such cases, standard filtered back-projection often results in poor quality reconstructions. Iterative reconstruction algorithms, such as model-based iterative reconstructions (MBIR), have demonstrated considerable success in producing high-quality reconstructions under such restrictions, but typically require high-performance computing resources with hundreds of compute nodes to solve the problem in a reasonable time. Here, tomoCAM, is introduced, a new GPU-accelerated implementation of model-based iterative reconstruction that leverages non-uniform fast Fourier transforms to efficiently compute Radon and back-projection operators and asynchronous memory transfers to maximize the throughput to the GPU memory. The resulting code is significantly faster than traditional MBIR codes and delivers the reconstructive improvement offered by MBIR with affordable computing time and resources. tomoCAM has a Python front-end, allowing access from Jupyter-based frameworks, providing straightforward integration into existing workflows at synchrotron facilities.urn:issn:1600-5775text/htmltomoCAM is an open-source implementation of model-based iterative reconstructions that reformulates the iterative tomographic reconstruction problem to leverage the faster time complexity of non-uniform fast Fourier transforms. Moreover, it harnesses the computational capabilities of modern GPUs, leading to significant performance gains compared with currently available publicly accessible tools. tomoCAM is accessible via Python and is compatible with NumPy, facilitating its incorporation into pre-existing workflows at synchrotron light sources.2024-01-01X-RAY TOMOGRAPHY; MICRO-CT; SYNCHROTRON TOMOGRAPHY; GPU; MBIR; NANO-CT; TOMOGRAPHIC RECONSTRUCTIONtomoCAM: fast model-based iterative reconstruction via GPU acceleration and non-uniform fast Fourier transformsInternational Union of CrystallographyKumar, D.Parkinson, D.Y.Donatelli, J.J.doi:10.1107/S1600577523008962enhttps://creativecommons.org/licenses/by/4.0/9431Journal of Synchrotron RadiationJanuary 2024med@iucr.org2024-01-011600-57751https://creativecommons.org/licenses/by/4.0/85research papers1600-5775Opportunities and new developments for the study of surfaces and interfaces in soft condensed matter at the SIRIUS beamline of Synchrotron SOLEIL
http://scripts.iucr.org/cgi-bin/paper?ay5620
The SIRIUS beamline of Synchrotron SOLEIL is dedicated to X-ray scattering and spectroscopy of surfaces and interfaces, covering the tender to mid-hard X-ray range (1.1–13 keV). The beamline has hosted a wide range of experiments in the field of soft interfaces and beyond, providing various grazing-incidence techniques such as diffraction and wide-angle scattering (GIXD/GIWAXS), small-angle scattering (GISAXS) and X-ray fluorescence in total reflection (TXRF). SIRIUS also offers specific sample environments tailored for in situ complementary experiments on solid and liquid surfaces. Recently, the beamline has added compound refractive lenses associated with a transfocator, allowing for the X-ray beam to be focused down to 10 µm × 10 µm while maintaining a reasonable flux on the sample. This new feature opens up new possibilities for faster GIXD measurements at the liquid–air interface and for measurements on samples with narrow geometries.textThe SIRIUS beamline of Synchrotron SOLEIL is dedicated to X-ray scattering and spectroscopy of surfaces and interfaces, covering the tender to mid-hard X-ray range (1.1–13 keV). The beamline has hosted a wide range of experiments in the field of soft interfaces and beyond, providing various grazing-incidence techniques such as diffraction and wide-angle scattering (GIXD/GIWAXS), small-angle scattering (GISAXS) and X-ray fluorescence in total reflection (TXRF). SIRIUS also offers specific sample environments tailored for in situ complementary experiments on solid and liquid surfaces. Recently, the beamline has added compound refractive lenses associated with a transfocator, allowing for the X-ray beam to be focused down to 10 µm × 10 µm while maintaining a reasonable flux on the sample. This new feature opens up new possibilities for faster GIXD measurements at the liquid–air interface and for measurements on samples with narrow geometries.urn:issn:1600-5775text/htmlThe main characteristics of the beamline SIRIUS at Synchrotron SOLEIL relevant for soft matter science are presented, as well as recent developments of new sample environments and of X-ray focusing with compound refractive lenses.2024-01-01BEAMLINE; SOFT CONDENSED MATTER; GRAZING-INCIDENCE TECHNIQUES; TXRF; SURFACE SCIENCEOpportunities and new developments for the study of surfaces and interfaces in soft condensed matter at the SIRIUS beamline of Synchrotron SOLEILInternational Union of CrystallographyHemmerle, A.Aubert, N.Moreno, T.Kékicheff, P.Heinrich, B.Spagnoli, S.Goldmann, M.Ciatto, G.Fontaine, P.doi:10.1107/S1600577523008810enhttps://creativecommons.org/licenses/by/4.0/beamlines162https://creativecommons.org/licenses/by/4.0/11600-5775Journal of Synchrotron Radiation31176January 20242024-01-011600-5775med@iucr.orgInvestigation of the mechanical work during ultrasonic fatigue loading using pulsed time-resolved X-ray diffraction
http://scripts.iucr.org/cgi-bin/paper?vy5014
In the energy production and transportation industries, numerous metallic structures may be subjected to at least several billions of cycles, i.e. loaded in the very high cycle fatigue domain (VHCF). Therefore, to design structures in the VHCF domain, a reliable methodology is necessary. One useful quantity to characterize plastic activity at the microscopic scale and fatigue damage evolution is the mechanical work supplied to a material. However, the estimation of this mechanical work in a metal during ultrasonic fatigue tests remains challenging. This paper aims to present an innovative methodology to quantify this. An experimental procedure was developed to estimate the mechanical work from stress and total strain evolution measurements during one loading cycle with a time accuracy of about 50 ns. This was achieved by conducting time-resolved X-ray diffraction coupled to strain gauge measurements at a synchrotron facility working in pulsed mode (single-bunch mode).textIn the energy production and transportation industries, numerous metallic structures may be subjected to at least several billions of cycles, i.e. loaded in the very high cycle fatigue domain (VHCF). Therefore, to design structures in the VHCF domain, a reliable methodology is necessary. One useful quantity to characterize plastic activity at the microscopic scale and fatigue damage evolution is the mechanical work supplied to a material. However, the estimation of this mechanical work in a metal during ultrasonic fatigue tests remains challenging. This paper aims to present an innovative methodology to quantify this. An experimental procedure was developed to estimate the mechanical work from stress and total strain evolution measurements during one loading cycle with a time accuracy of about 50 ns. This was achieved by conducting time-resolved X-ray diffraction coupled to strain gauge measurements at a synchrotron facility working in pulsed mode (single-bunch mode).urn:issn:1600-5775text/htmlThe development of a time-resolved X-ray diffraction technique using synchrotron radiation in pulsed mode to estimate the stress and the mechanical work during an ultrasonic fatigue test is presented.2024-01-01X-RAY DIFFRACTION; ULTRASONIC FATIGUE MACHINE; VERY HIGH CYCLE FATIGUE; PUMP-PROBE METHOD; PULSED X-RAY SOURCEInvestigation of the mechanical work during ultrasonic fatigue loading using pulsed time-resolved X-ray diffractionInternational Union of CrystallographyJacquemain, V.Cheuleu, C.Ranc, N.Castelnau, O.Michel, V.Vinci, D.Favier, V.Mocuta, C.Thiaudiere, D.doi:10.1107/S1600577523008767enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org2024-01-011600-577531Journal of Synchrotron Radiation27January 20241600-5775https://creativecommons.org/licenses/by/4.0/117research papersBeagle: a near-edge X-ray absorption fine-structure spectroscopy data processing solution for beamline experiments at Pohang Accelerator Laboratory
http://scripts.iucr.org/cgi-bin/paper?vy5015
Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is a powerful tool for identifying chemical bonding states at synchrotron radiation facilities. Advances in new materials require researchers in both academia and industry to measure tens to hundreds of samples during the available beam time on a synchrotron beamline, which is typically allocated to users. Automated measurement methods, along with analysis software, have been developed for beamlines. Automated measurements facilitate high-throughput experiments and accumulate vast amounts of measured spectral data. The analysis software supports various functions for analyzing the experimental data; however, these analysis methods are complicated, and learning them can be time-consuming. To process large amounts of spectral data, a new analysis software, dedicated to NEXAFS spectroscopy, that is easy to use and can provide results in a short time is desired. Herein, the development of Beagle is described, software calculating molecular orientation from NEXAFS spectroscopy data that can report results in a short time comparable with that required to measure one sample at the beamline. It was designed to progress in a single sequence from data loading to the printing of the results with a `click of a button'. The functions of the software include recognizing the dataset, correcting the background, normalizing the plot, calculating the electron yield and determining the molecular orientation. The analysis results can be saved as {\tt{.txt}} files (spectral data), {\tt{.pdf}} files (graphic images) and Origin files (spectral data and graphic images).textNear-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is a powerful tool for identifying chemical bonding states at synchrotron radiation facilities. Advances in new materials require researchers in both academia and industry to measure tens to hundreds of samples during the available beam time on a synchrotron beamline, which is typically allocated to users. Automated measurement methods, along with analysis software, have been developed for beamlines. Automated measurements facilitate high-throughput experiments and accumulate vast amounts of measured spectral data. The analysis software supports various functions for analyzing the experimental data; however, these analysis methods are complicated, and learning them can be time-consuming. To process large amounts of spectral data, a new analysis software, dedicated to NEXAFS spectroscopy, that is easy to use and can provide results in a short time is desired. Herein, the development of Beagle is described, software calculating molecular orientation from NEXAFS spectroscopy data that can report results in a short time comparable with that required to measure one sample at the beamline. It was designed to progress in a single sequence from data loading to the printing of the results with a `click of a button'. The functions of the software include recognizing the dataset, correcting the background, normalizing the plot, calculating the electron yield and determining the molecular orientation. The analysis results can be saved as {\tt{.txt}} files (spectral data), {\tt{.pdf}} files (graphic images) and Origin files (spectral data and graphic images).urn:issn:1600-5775text/htmlA new software, Beagle, has been developed to analyze NEXAFS spectroscopy at PAL. It calculates molecular orientation for high-throughput experiments, handling more than 100 samples per day.2024-01-01NEXAFS SPECTROSCOPY; HIGH-THROUGHPUT ANALYSIS; SYNCHROTRON RADIATION BEAMLINE; SPECTRAL DATA ANALYSIS SOFTWAREBeagle: a near-edge X-ray absorption fine-structure spectroscopy data processing solution for beamline experiments at Pohang Accelerator LaboratoryInternational Union of CrystallographyPark, J.Y.Lee, M.Jeong, S.-H.Lee, H.-K.doi:10.1107/S1600577523008755enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org2024-01-011600-577531Journal of Synchrotron RadiationJanuary 20241600-57751https://creativecommons.org/licenses/by/4.0/computer programsImprovement of ultra-small-angle XPCS with the Extremely Brilliant Source
http://scripts.iucr.org/cgi-bin/paper?ju5056
Recent technical developments and the performance of the X-ray photon correlation spectroscopy (XPCS) method over the ultra-small-angle range with the Extremely Brilliant Source (EBS) at the ESRF are described. With higher monochromatic coherent photon flux (∼1012 photons s−1) provided by the EBS and the availability of a fast pixel array detector (EIGER 500K detector operating at 23000 frames s−1), XPCS has become more competitive for probing faster dynamics in relatively dilute suspensions. One of the goals of the present development is to increase the user-friendliness of the method. This is achieved by means of a Python-based graphical user interface that enables online visualization and analysis of the processed data. The improved performance of XPCS on the Time-Resolved Ultra-Small-Angle X-ray Scattering instrument (ID02 beamline) is demonstrated using dilute model colloidal suspensions in several different applications.textRecent technical developments and the performance of the X-ray photon correlation spectroscopy (XPCS) method over the ultra-small-angle range with the Extremely Brilliant Source (EBS) at the ESRF are described. With higher monochromatic coherent photon flux (∼1012 photons s−1) provided by the EBS and the availability of a fast pixel array detector (EIGER 500K detector operating at 23000 frames s−1), XPCS has become more competitive for probing faster dynamics in relatively dilute suspensions. One of the goals of the present development is to increase the user-friendliness of the method. This is achieved by means of a Python-based graphical user interface that enables online visualization and analysis of the processed data. The improved performance of XPCS on the Time-Resolved Ultra-Small-Angle X-ray Scattering instrument (ID02 beamline) is demonstrated using dilute model colloidal suspensions in several different applications.urn:issn:1600-5775text/htmlThe technical performance of ultra-small-angle X-ray photon correlation spectroscopy with the ESRF Extremely Brilliant Source is presented. The brighter X-ray source together with advanced pixel array detectors enable investigations of faster dynamics in relatively dilute suspensions by this method.2024-01-01XPCS; COHERENT X-RAY SCATTERING; SPECKLE CONTRAST; UA-XPCS; USAXSImprovement of ultra-small-angle XPCS with the Extremely Brilliant SourceInternational Union of CrystallographyChèvremont, W.Zinn, T.Narayanan, T.doi:10.1107/S1600577523008627enhttps://creativecommons.org/licenses/by/4.0/January 202431Journal of Synchrotron Radiation761600-57752024-01-01med@iucr.org65research papershttps://creativecommons.org/licenses/by/4.0/11600-5775The emergence of super-resolution beyond the probe size in scanning 3DXRD microscopy
http://scripts.iucr.org/cgi-bin/paper?ay5617
The spatial resolution in scanning-based two-dimensional microscopy is normally limited by the size of the probe, thereby a smaller probe is a prerequisite for enhancing the spatial resolution. For three-dimensional microscopy that combines translation and rotation motions of a specimen, however, complex trajectories of the probe highly overlap in the specimen, which could change the postulate above. Here, the spatial resolution achieved in scanning three-dimensional X-ray diffraction (s3DXRD) microscopy is investigated. In this method, the most appropriate orientation of the pixel in the specimen coordinate is selected by comparing the completeness of diffraction peaks with theory. Therefore, the superposed area of the beam trajectory has a strong effect on the spatial resolution, in terms of the completeness of diffraction peaks. It was found that the highly superposed area by the incident X-rays, which has the highest completeness factor in the pixel of the specimen, is much smaller than the X-ray probe size, and that sub-pixel analysis by dividing a pixel into small pieces leads to drastic improvement of the spatial resolution in s3DXRD.textThe spatial resolution in scanning-based two-dimensional microscopy is normally limited by the size of the probe, thereby a smaller probe is a prerequisite for enhancing the spatial resolution. For three-dimensional microscopy that combines translation and rotation motions of a specimen, however, complex trajectories of the probe highly overlap in the specimen, which could change the postulate above. Here, the spatial resolution achieved in scanning three-dimensional X-ray diffraction (s3DXRD) microscopy is investigated. In this method, the most appropriate orientation of the pixel in the specimen coordinate is selected by comparing the completeness of diffraction peaks with theory. Therefore, the superposed area of the beam trajectory has a strong effect on the spatial resolution, in terms of the completeness of diffraction peaks. It was found that the highly superposed area by the incident X-rays, which has the highest completeness factor in the pixel of the specimen, is much smaller than the X-ray probe size, and that sub-pixel analysis by dividing a pixel into small pieces leads to drastic improvement of the spatial resolution in s3DXRD.urn:issn:1600-5775text/htmlIt has been believed that the resolution in scanning-based microscopy is defined by the probe size, but this postulate is not valid in scanning three-dimensional X-ray diffraction (3DXRD) microscopy that combines the translation and rotation motions of a specimen. Numerical simulation shows that the spatial resolution in scanning 3DXRD microscopy surpasses the probe size due to the superposition of the X-ray beam trajectories.2023-10-17SCANNING 3DXRD; SUPER RESOLUTION; BEAM TRAJECTORYThe emergence of super-resolution beyond the probe size in scanning 3DXRD microscopyInternational Union of CrystallographyKim, J.Hayashi, Y.Yabashi, M.doi:10.1107/S1600577523008597enhttps://creativecommons.org/licenses/by/4.0/111330Journal of Synchrotron RadiationNovember 20232023-10-171600-5775med@iucr.org1108research papers6https://creativecommons.org/licenses/by/4.0/1600-5775The new small-angle X-ray scattering beamline for materials research at PETRA III: SAXSMAT beamline P62
http://scripts.iucr.org/cgi-bin/paper?ay5619
The SAXSMAT beamline P62 (Small-Angle X-ray Scattering beamline for Materials Research) is a new beamline at the high-energy storage ring PETRA III at DESY. This beamline is dedicated to combined small- and wide-angle X-ray scattering (SAXS/WAXS) techniques for both soft and hard condensed matter systems. It works mainly in transmission geometry. The beamline covers an energy range from 3.5 keV to 35.0 keV, which fulfills the requirements of the user community to perform anomalous scattering experiments. Mirrors are used to reduce the intensity of higher harmonics. Furthermore, the mirrors and 2D compound refracting lenses can focus the beam down to a few micrometres at the sample position. This option with the high photon flux enables also SAXS/WAXS tensor tomography experiments to be performed at this new beamline in a relatively short time. The first SAXS/WAXS pattern was collected in August 2021, while the first user experiment was carried out two months later. Since January 2022 the beamline has been in regular user operation mode. In this paper the beamline optics and the SAXS/WAXS instrument are described and two examples are briefly shown.textThe SAXSMAT beamline P62 (Small-Angle X-ray Scattering beamline for Materials Research) is a new beamline at the high-energy storage ring PETRA III at DESY. This beamline is dedicated to combined small- and wide-angle X-ray scattering (SAXS/WAXS) techniques for both soft and hard condensed matter systems. It works mainly in transmission geometry. The beamline covers an energy range from 3.5 keV to 35.0 keV, which fulfills the requirements of the user community to perform anomalous scattering experiments. Mirrors are used to reduce the intensity of higher harmonics. Furthermore, the mirrors and 2D compound refracting lenses can focus the beam down to a few micrometres at the sample position. This option with the high photon flux enables also SAXS/WAXS tensor tomography experiments to be performed at this new beamline in a relatively short time. The first SAXS/WAXS pattern was collected in August 2021, while the first user experiment was carried out two months later. Since January 2022 the beamline has been in regular user operation mode. In this paper the beamline optics and the SAXS/WAXS instrument are described and two examples are briefly shown.urn:issn:1600-5775text/htmlThe SAXSMAT beamline P62 (Small-Angle X-ray Scattering beamline for Materials Research) is a new beamline at the high-energy storage ring PETRA III at DESY. This beamline is dedicated to combined small- and wide-angle X-ray scattering (SAXS/WAXS) techniques for both soft and hard condensed matter systems.2023-10-20SAXS; WAXS; SAXS TENSOR TOMOGRAPHY; SAXS-TT; COMPUTED TOMOGRAPHY; ANOMALOUS SCATTERING; ASAXS; SAXS-CTThe new small-angle X-ray scattering beamline for materials research at PETRA III: SAXSMAT beamline P62International Union of CrystallographyHaas, S.Sun, X.Conceição, A.L.C.Horbach, J.Pfeffer, S.doi:10.1107/S1600577523008603enhttps://creativecommons.org/licenses/by/4.0/1167Journal of Synchrotron Radiation30November 20232023-10-201600-5775med@iucr.orgbeamlines11566https://creativecommons.org/licenses/by/4.0/1600-5775synapse: interactive support on photoemission spectroscopy measurement and analysis for non-expert users
http://scripts.iucr.org/cgi-bin/paper?ve5171
Photoemission spectroscopy, an experimental method based on the photoelectric effect, is now an indispensable technique used in various fields such as materials science, life science, medicine and nanotechnology. However, part of the experimental process of photoemission spectroscopy relies on experience and intuition, which is obviously a problem for novice users. In particular, photoemission spectroscopy experiments using high-brilliance synchrotron radiation as a light source are not easy for novice users because measurements must be performed quickly and accurately as scheduled within a limited experimental period. In addition, research on the application of information science methods to quantum data measurement, such as photoemission spectroscopy, is mainly aimed at the development of analysis methods, and few attempts have been made to clarify the problems faced by users who lack experience. In this study, the problems faced by novice users of photoemission spectroscopy are identified, and a native application named synapse with functions to solve these problems is implemented and evaluated qualitatively and quantitatively. This paper describes the contents of an interview survey, the functional design and the implementation of the application synapse based on the interview survey, and results and discussion of the evaluation experiment.textPhotoemission spectroscopy, an experimental method based on the photoelectric effect, is now an indispensable technique used in various fields such as materials science, life science, medicine and nanotechnology. However, part of the experimental process of photoemission spectroscopy relies on experience and intuition, which is obviously a problem for novice users. In particular, photoemission spectroscopy experiments using high-brilliance synchrotron radiation as a light source are not easy for novice users because measurements must be performed quickly and accurately as scheduled within a limited experimental period. In addition, research on the application of information science methods to quantum data measurement, such as photoemission spectroscopy, is mainly aimed at the development of analysis methods, and few attempts have been made to clarify the problems faced by users who lack experience. In this study, the problems faced by novice users of photoemission spectroscopy are identified, and a native application named synapse with functions to solve these problems is implemented and evaluated qualitatively and quantitatively. This paper describes the contents of an interview survey, the functional design and the implementation of the application synapse based on the interview survey, and results and discussion of the evaluation experiment.urn:issn:1600-5775text/htmlProblems faced by novice users of photoemission spectroscopy are identified, and a native application named synapse with functions to solve these problems is implemented and evaluated qualitatively and quantitatively.2023-10-27PHOTOEMISSION SPECTROSCOPY; SYNCHROTRON RADIATION; USER INTERFACE; DATA ANALYSISsynapse: interactive support on photoemission spectroscopy measurement and analysis for non-expert usersInternational Union of CrystallographyMasuda, T.Kobayashi, M.Yatani, K.doi:10.1107/S1600577523008305enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752023-10-27November 2023113430Journal of Synchrotron Radiation1600-57756https://creativecommons.org/licenses/by/4.0/research papers1127Multiplexed emitting system for an energy-recovery-linac-based coherent light source
http://scripts.iucr.org/cgi-bin/paper?yi5140
Recently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUV and X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at the MW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources.textRecently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUV and X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at the MW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources.urn:issn:1600-5775text/htmlThe design of a multiplexed emitting system based on an energy recovery linac is presented. Five radiation pulses with a central wavelength of 13.5 nm and peak power at the MW level have been produced by the same electron beam via this system.2023-10-19ENERGY RECOVER LINAC; MULTI-BEAMLINE OPERATION; COHERENT RADIATION; ANGULAR-DISPERSION-INDUCED MICROBUNCHING; MULTI-BEND ACHROMATMultiplexed emitting system for an energy-recovery-linac-based coherent light sourceInternational Union of CrystallographyCao, L.Liu, J.Wang, Z.Huang, D.Feng, C.Zhao, Z.doi:10.1107/S1600577523008263enhttps://creativecommons.org/licenses/by/4.0/1054research papers6https://creativecommons.org/licenses/by/4.0/1600-5775November 20231063Journal of Synchrotron Radiation301600-57752023-10-19med@iucr.orgExperimental capabilities for liquid jet samples at sub-MHz rates at the FXE Instrument at European XFEL
http://scripts.iucr.org/cgi-bin/paper?ok5101
The Femtosecond X-ray Experiments (FXE) instrument at the European X-ray Free-Electron Laser (EuXFEL) provides an optimized platform for investigations of ultrafast physical, chemical and biological processes. It operates in the energy range 4.7–20 keV accommodating flexible and versatile environments for a wide range of samples using diverse ultrafast X-ray spectroscopic, scattering and diffraction techniques. FXE is particularly suitable for experiments taking advantage of the sub-MHz repetition rates provided by the EuXFEL. In this paper a dedicated setup for studies on ultrafast biological and chemical dynamics in solution phase at sub-MHz rates at FXE is presented. Particular emphasis on the different liquid jet sample delivery options and their performance is given. Our portfolio of high-speed jets compatible with sub-MHz experiments includes cylindrical jets, gas dynamic virtual nozzles and flat jets. The capability to perform multi-color X-ray emission spectroscopy (XES) experiments is illustrated by a set of measurements using the dispersive X-ray spectrometer in von Hamos geometry. Static XES data collected using a multi-crystal scanning Johann-type spectrometer are also presented. A few examples of experimental results on ultrafast time-resolved X-ray emission spectroscopy and wide-angle X-ray scattering at sub-MHz pulse repetition rates are given.textThe Femtosecond X-ray Experiments (FXE) instrument at the European X-ray Free-Electron Laser (EuXFEL) provides an optimized platform for investigations of ultrafast physical, chemical and biological processes. It operates in the energy range 4.7–20 keV accommodating flexible and versatile environments for a wide range of samples using diverse ultrafast X-ray spectroscopic, scattering and diffraction techniques. FXE is particularly suitable for experiments taking advantage of the sub-MHz repetition rates provided by the EuXFEL. In this paper a dedicated setup for studies on ultrafast biological and chemical dynamics in solution phase at sub-MHz rates at FXE is presented. Particular emphasis on the different liquid jet sample delivery options and their performance is given. Our portfolio of high-speed jets compatible with sub-MHz experiments includes cylindrical jets, gas dynamic virtual nozzles and flat jets. The capability to perform multi-color X-ray emission spectroscopy (XES) experiments is illustrated by a set of measurements using the dispersive X-ray spectrometer in von Hamos geometry. Static XES data collected using a multi-crystal scanning Johann-type spectrometer are also presented. A few examples of experimental results on ultrafast time-resolved X-ray emission spectroscopy and wide-angle X-ray scattering at sub-MHz pulse repetition rates are given.urn:issn:1600-5775text/htmlA platform for experiments investigating the ultrafast dynamics of biological and chemical systems in solution phase at sub-MHz rates at the FXE Instrument at European XFEL is presented. Examples of fs-resolved X-ray emission spectroscopy and wide-angle X-ray scattering on typical spin-crossovers are given.2023-10-20X-RAY FREE-ELECTRON LASER; XES; WAXS; XRD; UTRAFAST SCIENCE; PUMP-PROBE; LIQUID JETSExperimental capabilities for liquid jet samples at sub-MHz rates at the FXE Instrument at European XFELInternational Union of CrystallographyLima, F.A.Otte, F.Vakili, M.Ardana-Lamas, F.Biednov, M.Dall'Antonia, F.Frankenberger, P.Gawelda, W.Gelisio, L.Han, H.Huang, X.Jiang, Y.Kloos, M.Kluyver, T.Knoll, M.Kubicek, K.Bermudez Macias, I.J.Schulz, J.Turkot, O.Uemura, Y.Valerio, J.Wang, H.Yousef, H.Zalden, P.Khakhulin, D.Bressler, C.Milne, C.doi:10.1107/S1600577523008159enhttps://creativecommons.org/licenses/by/4.0/1168beamlineshttps://creativecommons.org/licenses/by/4.0/61600-577530Journal of Synchrotron Radiation1182November 20232023-10-201600-5775med@iucr.orgSparse-view synchrotron X-ray tomographic reconstruction with learning-based sinogram synthesis
http://scripts.iucr.org/cgi-bin/paper?tv5044
Synchrotron radiation can be used as a light source in X-ray microscopy to acquire a high-resolution image of a microscale object for tomography. However, numerous projections must be captured for a high-quality tomographic image to be reconstructed; thus, image acquisition is time consuming. Such dense imaging is not only expensive and time consuming but also results in the target receiving a large dose of radiation. To resolve these problems, sparse acquisition techniques have been proposed; however, the generated images often have many artefacts and are noisy. In this study, a deep-learning-based approach is proposed for the tomographic reconstruction of sparse-view projections that are acquired with a synchrotron light source; this approach proceeds as follows. A convolutional neural network (CNN) is used to first interpolate sparse X-ray projections and then synthesize a sufficiently large set of images to produce a sinogram. After the sinogram is constructed, a second CNN is used for error correction. In experiments, this method successfully produced high-quality tomography images from sparse-view projections for two data sets comprising Drosophila and mouse tomography images. However, the initial results for the smaller mouse data set were poor; therefore, transfer learning was used to apply the Drosophila model to the mouse data set, greatly improving the quality of the reconstructed sinogram. The method could be used to achieve high-quality tomography while reducing the radiation dose to imaging subjects and the imaging time and cost.textSynchrotron radiation can be used as a light source in X-ray microscopy to acquire a high-resolution image of a microscale object for tomography. However, numerous projections must be captured for a high-quality tomographic image to be reconstructed; thus, image acquisition is time consuming. Such dense imaging is not only expensive and time consuming but also results in the target receiving a large dose of radiation. To resolve these problems, sparse acquisition techniques have been proposed; however, the generated images often have many artefacts and are noisy. In this study, a deep-learning-based approach is proposed for the tomographic reconstruction of sparse-view projections that are acquired with a synchrotron light source; this approach proceeds as follows. A convolutional neural network (CNN) is used to first interpolate sparse X-ray projections and then synthesize a sufficiently large set of images to produce a sinogram. After the sinogram is constructed, a second CNN is used for error correction. In experiments, this method successfully produced high-quality tomography images from sparse-view projections for two data sets comprising Drosophila and mouse tomography images. However, the initial results for the smaller mouse data set were poor; therefore, transfer learning was used to apply the Drosophila model to the mouse data set, greatly improving the quality of the reconstructed sinogram. The method could be used to achieve high-quality tomography while reducing the radiation dose to imaging subjects and the imaging time and cost.urn:issn:1600-5775text/htmlThis article proposes a deep-learning-based approach for synchrotron X-ray computed tomography with sparse-view projections. The experimental results indicate that tomographic images can be reconstructed by 75 X-ray projections without obvious streak artefacts and noise.2023-10-17SPARSE-VIEW COMPUTED TOMOGRAPHY; SYNCHROTRON X-RAY COMPUTED TOMOGRAPHY; DEEP LEARNING; VIEW INTERPOLATION; SINOGRAM SYNTHESISSparse-view synchrotron X-ray tomographic reconstruction with learning-based sinogram synthesisInternational Union of CrystallographyCheng, C.-C.Chiang, M.-H.Yeh, C.-H.Lee, T.-T.Ching, Y.-T.Hwu, Y.Chiang, A.-S.doi:10.1107/S1600577523008032enhttps://creativecommons.org/licenses/by/4.0/1600-57751135research papershttps://creativecommons.org/licenses/by/4.0/61600-57752023-10-17med@iucr.orgNovember 2023Journal of Synchrotron Radiation301142Correction and integration of solid-angle data from the azimuthally resolving 2D detector at ID06-LVP, ESRF
http://scripts.iucr.org/cgi-bin/paper?yi5142
The unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0 m), the system covers an area of near 2.5 m2 (100 Mpx square equivalent), to 0.65 Å resolution, at 53 keV from a total dataset of some 312 Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from <20° to ∼1° over the full range of the detector surface. A full 2θ–intensity data collection at static azimuth takes 1–3 s typically, and can be reduced to ms−1 rates for measurements requiring time-rate determination. A full solid-angle collection can be completed in a minute. Sample detector distances are accessible from 1.6 m to 4.0 m.textThe unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0 m), the system covers an area of near 2.5 m2 (100 Mpx square equivalent), to 0.65 Å resolution, at 53 keV from a total dataset of some 312 Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from <20° to ∼1° over the full range of the detector surface. A full 2θ–intensity data collection at static azimuth takes 1–3 s typically, and can be reduced to ms−1 rates for measurements requiring time-rate determination. A full solid-angle collection can be completed in a minute. Sample detector distances are accessible from 1.6 m to 4.0 m.urn:issn:1600-5775text/htmlCorrections that allow for high-precision integration of part or full solid-angle datasets from the long-aspect-ratio Pilatus 900k-W device at ESRF beamline ID06-LVP are presented.2023-10-17DIFFRACTION; DETECTOR; BEAMLINE; HIGH PRESSURE; EXTREME CONDITIONSCorrection and integration of solid-angle data from the azimuthally resolving 2D detector at ID06-LVP, ESRFInternational Union of CrystallographyCrichton, W.A.Kieffer, J.Wattecamps, P.Valls, V.Berruyer, G.Ruat, M.Favre-Nicolin, V.doi:10.1107/S1600577523008020enhttps://creativecommons.org/licenses/by/4.0/6https://creativecommons.org/licenses/by/4.0/1149beamlines1600-5775November 2023115530Journal of Synchrotron Radiationmed@iucr.org1600-57752023-10-17Spectral-brightness optimization of an X-ray free-electron laser by machine-learning-based tuning
http://scripts.iucr.org/cgi-bin/paper?yn5102
A machine-learning-based beam optimizer has been implemented to maximize the spectral brightness of the X-ray free-electron laser (XFEL) pulses of SACLA. A new high-resolution single-shot inline spectrometer capable of resolving features of the order of a few electronvolts was employed to measure and evaluate XFEL pulse spectra. Compared with a simple pulse-energy-based optimization, the spectral width was narrowed by half and the spectral brightness was improved by a factor of 1.7. The optimizer significantly contributes to efficient machine tuning and improvement of XFEL performance at SACLA.textA machine-learning-based beam optimizer has been implemented to maximize the spectral brightness of the X-ray free-electron laser (XFEL) pulses of SACLA. A new high-resolution single-shot inline spectrometer capable of resolving features of the order of a few electronvolts was employed to measure and evaluate XFEL pulse spectra. Compared with a simple pulse-energy-based optimization, the spectral width was narrowed by half and the spectral brightness was improved by a factor of 1.7. The optimizer significantly contributes to efficient machine tuning and improvement of XFEL performance at SACLA.urn:issn:1600-5775text/htmlSpectral-brightness optimization was performed by using a machine-learning-based beam optimizer and a new high-resolution inline spectrometer.2023-10-27X-RAY FREE-ELECTRON LASERS; MACHINE LEARNING; BEAM TUNING; SACLA; SPECTRAL-BRIGHTNESS OPTIMIZATION; SINGLE-SHOT INLINE SPECTROMETERSSpectral-brightness optimization of an X-ray free-electron laser by machine-learning-based tuningInternational Union of CrystallographyIwai, E.Inoue, I.Maesaka, H.Inagaki, T.Yabashi, M.Hara, T.Tanaka, H.doi:10.1107/S1600577523007737enhttps://creativecommons.org/licenses/by/4.0/November 2023105330Journal of Synchrotron Radiationmed@iucr.org1600-57752023-10-276https://creativecommons.org/licenses/by/4.0/research papers10481600-5775Passive doubly curved structures for determining clamping forces applied to X-ray optic assemblies
http://scripts.iucr.org/cgi-bin/paper?yi5141
Clamping of indirectly cryogenically cooled X-ray optics is required to ensure effective heat transfer between the optic and heat exchanger. However, clamping forces can result in distortion of the optical surface of monochromators and mirror systems, which causes angular distortions of the subsequent beam. As such, there is a need for greater understanding of how these optics are assembled and how this affects their performance throughout their life cycle. In this paper, the potential for non-contact, in-process monitoring of the clamping force both during and after assembly using an additively manufactured passive structure based on a doubly curved hyperbolic paraboloid and designed for application to the first crystal for the I20 monochromator at Diamond Light Source is investigated numerically and experimentally. The performance of the passive structure both pre- and post-cryogenic quenching is characterized experimentally. Laser displacement measurements reveal approximately 9 µm total displacement in the passive structure per 100 N of bolt preload, corresponding to an effective magnification of the preload adjustment of approximately 2.5×.textClamping of indirectly cryogenically cooled X-ray optics is required to ensure effective heat transfer between the optic and heat exchanger. However, clamping forces can result in distortion of the optical surface of monochromators and mirror systems, which causes angular distortions of the subsequent beam. As such, there is a need for greater understanding of how these optics are assembled and how this affects their performance throughout their life cycle. In this paper, the potential for non-contact, in-process monitoring of the clamping force both during and after assembly using an additively manufactured passive structure based on a doubly curved hyperbolic paraboloid and designed for application to the first crystal for the I20 monochromator at Diamond Light Source is investigated numerically and experimentally. The performance of the passive structure both pre- and post-cryogenic quenching is characterized experimentally. Laser displacement measurements reveal approximately 9 µm total displacement in the passive structure per 100 N of bolt preload, corresponding to an effective magnification of the preload adjustment of approximately 2.5×.urn:issn:1600-5775text/htmlA novel approach to in-process monitoring of clamping forces applied to indirectly cooled X-ray optics through use of an additively manufactured passive structure, based on a doubly curved hyperbolic paraboloid, is detailed. The results presented reveal accurate and repeatable displacement at the tip of the structure under preload, both pre- and post-cryogenic quenching, amplifying the adjustment reaction at the bolt by a factor of approximately 2.5.2023-10-10SILICON MONOCHROMATORS; X-RAY OPTICS; CLAMPING DISTORTIONPassive doubly curved structures for determining clamping forces applied to X-ray optic assembliesInternational Union of CrystallographyBainbridge, E.V.Griffiths, J.D.Patel, H.Clunan, J.Docker, P.doi:10.1107/S1600577523007579enhttps://creativecommons.org/licenses/by/4.0/30Journal of Synchrotron Radiation1148November 2023med@iucr.org2023-10-101600-5775https://creativecommons.org/licenses/by/4.0/61143short communications1600-5775At-wavelength characterization of X-ray wavefronts in Bragg diffraction from crystals
http://scripts.iucr.org/cgi-bin/paper?mo5273
The advent of next-generation synchrotron radiation sources and X-ray free-electron lasers calls for high-quality Bragg-diffraction crystal optics to preserve the X-ray beam coherence and wavefront. This requirement brings new challenges in characterizing crystals in Bragg diffraction in terms of Bragg-plane height errors and wavefront phase distortions. Here, a quantitative methodology to characterize crystal optics using a state-of-the-art at-wavelength wavefront sensing technique and statistical analysis is proposed. The method was tested at the 1-BM-B optics testing beamline at the Advanced Photon Source for measuring silicon and diamond crystals in a self-referencing single-crystal mode and an absolute double-crystal mode. The phase error sensitivity of the technique is demonstrated to be at the λ/100 level required by most applications, such as the characterization of diamond crystals for cavity-based X-ray free-electron lasers.textThe advent of next-generation synchrotron radiation sources and X-ray free-electron lasers calls for high-quality Bragg-diffraction crystal optics to preserve the X-ray beam coherence and wavefront. This requirement brings new challenges in characterizing crystals in Bragg diffraction in terms of Bragg-plane height errors and wavefront phase distortions. Here, a quantitative methodology to characterize crystal optics using a state-of-the-art at-wavelength wavefront sensing technique and statistical analysis is proposed. The method was tested at the 1-BM-B optics testing beamline at the Advanced Photon Source for measuring silicon and diamond crystals in a self-referencing single-crystal mode and an absolute double-crystal mode. The phase error sensitivity of the technique is demonstrated to be at the λ/100 level required by most applications, such as the characterization of diamond crystals for cavity-based X-ray free-electron lasers.urn:issn:1600-5775text/htmlA quantitative methodology utilizing at-wavelength wavefront sensing is developed for characterizing X-ray wavefronts in Bragg diffraction from high-quality crystal optics for next-generation synchrotron radiation sources and X-ray free-electron lasers.2023-10-10WAVEFRONT SENSING; CRYSTAL DIFFRACTION; CODED MASK; PHASE ERROR; AT-WAVELENGTH METROLOGYAt-wavelength characterization of X-ray wavefronts in Bragg diffraction from crystalsInternational Union of CrystallographyShi, X.Qiao, Z.Pradhan, P.Liu, P.Assoufid, L.Kim, K.-J.Shvyd'ko, Y.doi:10.1107/S1600577523007531enhttps://creativecommons.org/licenses/by/4.0/November 2023Journal of Synchrotron Radiation301107med@iucr.org1600-57752023-10-10https://creativecommons.org/licenses/by/4.0/61100research papers1600-5775Monocrystalline diamond detector for online monitoring during synchrotron microbeam radiotherapy
http://scripts.iucr.org/cgi-bin/paper?ve5172
Microbeam radiation therapy (MRT) is a radiotherapy technique combining spatial fractionation of the dose distribution on a micrometric scale, X-rays in the 50–500 keV range and dose rates up to 16 × 103 Gy s−1. Nowadays, in vivo dosimetry remains a challenge due to the ultra-high radiation fluxes involved and the need for high-spatial-resolution detectors. The aim here was to develop a striped diamond portal detector enabling online microbeam monitoring during synchrotron MRT treatments. The detector, a 550 µm bulk monocrystalline diamond, is an eight-strip device, of height 3 mm, width 178 µm and with 60 µm spaced strips, surrounded by a guard ring. An eight-channel ASIC circuit for charge integration and digitization has been designed and tested. Characterization tests were performed at the ID17 biomedical beamline of the European Synchrotron Radiation Facility (ESRF). The detector measured direct and attenuated microbeams as well as interbeam fluxes with a precision level of 1%. Tests on phantoms (RW3 and anthropomorphic head phantoms) were performed and compared with simulations. Synchrotron radiation measurements were performed on an RW3 phantom for strips facing a microbeam and for strips facing an interbeam area. A 2% difference between experiments and simulations was found. In more complex geometries, a preliminary study showed that the absolute differences between simulated and recorded transmitted beams were within 2%. Obtained results showed the feasibility of performing MRT portal monitoring using a microstriped diamond detector. Online dosimetric measurements are currently ongoing during clinical veterinary trials at ESRF, and the next 153-strip detector prototype, covering the entire irradiation field, is being finalized at our institution.textMicrobeam radiation therapy (MRT) is a radiotherapy technique combining spatial fractionation of the dose distribution on a micrometric scale, X-rays in the 50–500 keV range and dose rates up to 16 × 103 Gy s−1. Nowadays, in vivo dosimetry remains a challenge due to the ultra-high radiation fluxes involved and the need for high-spatial-resolution detectors. The aim here was to develop a striped diamond portal detector enabling online microbeam monitoring during synchrotron MRT treatments. The detector, a 550 µm bulk monocrystalline diamond, is an eight-strip device, of height 3 mm, width 178 µm and with 60 µm spaced strips, surrounded by a guard ring. An eight-channel ASIC circuit for charge integration and digitization has been designed and tested. Characterization tests were performed at the ID17 biomedical beamline of the European Synchrotron Radiation Facility (ESRF). The detector measured direct and attenuated microbeams as well as interbeam fluxes with a precision level of 1%. Tests on phantoms (RW3 and anthropomorphic head phantoms) were performed and compared with simulations. Synchrotron radiation measurements were performed on an RW3 phantom for strips facing a microbeam and for strips facing an interbeam area. A 2% difference between experiments and simulations was found. In more complex geometries, a preliminary study showed that the absolute differences between simulated and recorded transmitted beams were within 2%. Obtained results showed the feasibility of performing MRT portal monitoring using a microstriped diamond detector. Online dosimetric measurements are currently ongoing during clinical veterinary trials at ESRF, and the next 153-strip detector prototype, covering the entire irradiation field, is being finalized at our institution.urn:issn:1600-5775text/htmlThe development of a striped diamond portal detector for online monitoring during synchrotron microbeam radiation therapy is described. Its feasibility, ongoing dosimetric measurements in clinical trials and a prototype for a larger detector currently in progress are also described.2023-10-10MONOCRYSTALLINE DIAMOND DETECTORS; SYNCHROTRON MICROBEAM RADIOTHERAPY; ONLINE DOSIMETRYMonocrystalline diamond detector for online monitoring during synchrotron microbeam radiotherapyInternational Union of Crystallographydi Franco, F.Rosuel, N.Gallin-Martel, L.Gallin-Martel, M.-L.Ghafooryan-Sangchooli, M.Keshmiri, S.Motte, J.-F.Muraz, J.-F.Pellicioli, P.Ruat, M.Serduc, R.Verry, C.Dauvergne, D.Adam, J.-F.doi:10.1107/S160057752300752Xenhttps://creativecommons.org/licenses/by/4.0/1600-57752023-10-10med@iucr.orgNovember 20231085Journal of Synchrotron Radiation301600-57751076research papers6https://creativecommons.org/licenses/by/4.0/Closing the loop: autonomous experiments enabled by machine-learning-based online data analysis in synchrotron beamline environments
http://scripts.iucr.org/cgi-bin/paper?ju5054
Recently, there has been significant interest in applying machine-learning (ML) techniques to the automated analysis of X-ray scattering experiments, due to the increasing speed and size at which datasets are generated. ML-based analysis presents an important opportunity to establish a closed-loop feedback system, enabling monitoring and real-time decision-making based on online data analysis. In this study, the incorporation of a combined one-dimensional convolutional neural network (CNN) and multilayer perceptron that is trained to extract physical thin-film parameters (thickness, density, roughness) and capable of taking into account prior knowledge is described. ML-based online analysis results are processed in a closed-loop workflow for X-ray reflectometry (XRR), using the growth of organic thin films as an example. Our focus lies on the beamline integration of ML-based online data analysis and closed-loop feedback. Our data demonstrate the accuracy and robustness of ML methods for analyzing XRR curves and Bragg reflections and its autonomous control over a vacuum deposition setup.textRecently, there has been significant interest in applying machine-learning (ML) techniques to the automated analysis of X-ray scattering experiments, due to the increasing speed and size at which datasets are generated. ML-based analysis presents an important opportunity to establish a closed-loop feedback system, enabling monitoring and real-time decision-making based on online data analysis. In this study, the incorporation of a combined one-dimensional convolutional neural network (CNN) and multilayer perceptron that is trained to extract physical thin-film parameters (thickness, density, roughness) and capable of taking into account prior knowledge is described. ML-based online analysis results are processed in a closed-loop workflow for X-ray reflectometry (XRR), using the growth of organic thin films as an example. Our focus lies on the beamline integration of ML-based online data analysis and closed-loop feedback. Our data demonstrate the accuracy and robustness of ML methods for analyzing XRR curves and Bragg reflections and its autonomous control over a vacuum deposition setup.urn:issn:1600-5775text/htmlA machine-learning-based closed-loop solution for reflectometry analysis in synchrotron beamline operation utilizing online data analysis is presented. This work focuses on the perspective of visiting facility users and strategies to provide an elementary data analysis in real time during the experiment without introducing the additional software dependencies in the beamline control software environment.2023-10-17MACHINE LEARNING; REFLECTOMETRY; AUTONOMOUS EXPERIMENTS; BEAMLINE CONTROL; XRR; CLOSED-LOOP CONTROLClosing the loop: autonomous experiments enabled by machine-learning-based online data analysis in synchrotron beamline environmentsInternational Union of CrystallographyPithan, L.Starostin, V.Mareček, D.Petersdorf, L.Völter, C.Munteanu, V.Jankowski, M.Konovalov, O.Gerlach, A.Hinderhofer, A.Murphy, B.Kowarik, S.Schreiber, F.doi:10.1107/S160057752300749Xenhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/61064research papersmed@iucr.org1600-57752023-10-17November 202330Journal of Synchrotron Radiation1075Online dynamic flat-field correction for MHz microscopy data at European XFEL
http://scripts.iucr.org/cgi-bin/paper?tv5047
The high pulse intensity and repetition rate of the European X-ray Free-Electron Laser (EuXFEL) provide superior temporal resolution compared with other X-ray sources. In combination with MHz X-ray microscopy techniques, it offers a unique opportunity to achieve superior contrast and spatial resolution in applications demanding high temporal resolution. In both live visualization and offline data analysis for microscopy experiments, baseline normalization is essential for further processing steps such as phase retrieval and modal decomposition. In addition, access to normalized projections during data acquisition can play an important role in decision-making and improve the quality of the data. However, the stochastic nature of X-ray free-electron laser sources hinders the use of standard flat-field normalization methods during MHz X-ray microscopy experiments. Here, an online (i.e. near real-time) dynamic flat-field correction method based on principal component analysis of dynamically evolving flat-field images is presented. The method is used for the normalization of individual X-ray projections and has been implemented as a near real-time analysis tool at the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument of EuXFEL.textThe high pulse intensity and repetition rate of the European X-ray Free-Electron Laser (EuXFEL) provide superior temporal resolution compared with other X-ray sources. In combination with MHz X-ray microscopy techniques, it offers a unique opportunity to achieve superior contrast and spatial resolution in applications demanding high temporal resolution. In both live visualization and offline data analysis for microscopy experiments, baseline normalization is essential for further processing steps such as phase retrieval and modal decomposition. In addition, access to normalized projections during data acquisition can play an important role in decision-making and improve the quality of the data. However, the stochastic nature of X-ray free-electron laser sources hinders the use of standard flat-field normalization methods during MHz X-ray microscopy experiments. Here, an online (i.e. near real-time) dynamic flat-field correction method based on principal component analysis of dynamically evolving flat-field images is presented. The method is used for the normalization of individual X-ray projections and has been implemented as a near real-time analysis tool at the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument of EuXFEL.urn:issn:1600-5775text/htmlA near real-time dynamic flat-field correction tool has been implemented to normalize individual X-ray projections for MHz microscopy data at the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography instrument of European XFEL.2023-09-20MHZ X-RAY MICROSCOPY; FLAT-FIELD CORRECTION; ONLINE DATA PROCESSING; X-RAY FREE-ELECTRON LASEROnline dynamic flat-field correction for MHz microscopy data at European XFELInternational Union of CrystallographyBirnsteinova, S.Ferreira de Lima, D.E.Sobolev, E.Kirkwood, H.J.Bellucci, V.Bean, R.J.Kim, C.Koliyadu, J.C.P.Sato, T.Dall'Antonia, F.Asimakopoulou, E.M.Yao, Z.Buakor, K.Zhang, Y.Meents, A.Chapman, H.N.Mancuso, A.P.Villanueva-Perez, P.Vagovič, P.doi:10.1107/S1600577523007336enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752023-09-20November 2023Journal of Synchrotron Radiation301600-5775https://creativecommons.org/licenses/by/4.0/6research papersResonant X-ray emission spectroscopy using self-seeded hard X-ray pulses at PAL-XFEL
http://scripts.iucr.org/cgi-bin/paper?ok5100
Self-seeded hard X-ray pulses at PAL-XFEL were used to commission a resonant X-ray emission spectroscopy experiment with a von Hamos spectrometer. The self-seeded beam, generated through forward Bragg diffraction of the [202] peak in a 100 µm-thick diamond crystal, exhibited an average bandwidth of 0.54 eV at 11.223 keV. A coordinated scanning scheme of electron bunch energy, diamond crystal angle and silicon monochromator allowed us to map the Ir Lβ2 X-ray emission lines of IrO2 powder across the Ir L3-absorption edge, from 11.212 to 11.242 keV with an energy step of 0.3 eV. This work provides a reference for hard X-ray emission spectroscopy experiments utilizing self-seeded pulses with a narrow bandwidth, eventually applicable for pump–probe studies in solid-state and diluted systems.textSelf-seeded hard X-ray pulses at PAL-XFEL were used to commission a resonant X-ray emission spectroscopy experiment with a von Hamos spectrometer. The self-seeded beam, generated through forward Bragg diffraction of the [202] peak in a 100 µm-thick diamond crystal, exhibited an average bandwidth of 0.54 eV at 11.223 keV. A coordinated scanning scheme of electron bunch energy, diamond crystal angle and silicon monochromator allowed us to map the Ir Lβ2 X-ray emission lines of IrO2 powder across the Ir L3-absorption edge, from 11.212 to 11.242 keV with an energy step of 0.3 eV. This work provides a reference for hard X-ray emission spectroscopy experiments utilizing self-seeded pulses with a narrow bandwidth, eventually applicable for pump–probe studies in solid-state and diluted systems.urn:issn:1600-5775text/htmlResonant X-ray emission spectroscopy using self-seeded hard X-ray pulses with precise photon energy control was successfully demonstrated at the PAL-XFEL. This achievement proves the feasibility of a self-seeded beam for advanced X-ray spectroscopy experiments.2023-09-22X-RAY FREE-ELECTRON LASER (XFEL); SELF-SEEDING; RESONANT X-RAY EMISSION SPECTROSCOPY (RXES); VON HAMOS SPECTROMETERResonant X-ray emission spectroscopy using self-seeded hard X-ray pulses at PAL-XFELInternational Union of CrystallographyChoi, T.-K.Park, J.Kim, G.Jang, H.Park, S.-Y.Sohn, J.H.Cho, B.I.Kim, H.Kim, K.S.Nam, I.Chun, S.H.doi:10.1107/S1600577523007312enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/61038research papersmed@iucr.org1600-57752023-09-22November 202330Journal of Synchrotron Radiation1047In situ synchrotron X-ray total scattering measurements and analysis of colloidal CsPbX3 nanocrystals during flow synthesis
http://scripts.iucr.org/cgi-bin/paper?vl5011
In situ X-ray scattering measurements of CsPbX3 (X = Cl, Br, I) nanocrystal formation and halide exchange at NSLS-II beamlines were performed in an automated flow reactor. Total scattering measurements were performed at the 28-ID-2 (XPD) beamline and small-angle X-ray scattering at the 16-ID (LiX) beamline. Nanocrystal structural parameters of interest, including size, size distribution and atomic structure, were extracted from modeling the total scattering data. The results highlight the potential of these beamlines and the measurement protocols described in this study for studying dynamic processes of colloidal nanocrystal synthesis in solution with timescales on the order of seconds.textIn situ X-ray scattering measurements of CsPbX3 (X = Cl, Br, I) nanocrystal formation and halide exchange at NSLS-II beamlines were performed in an automated flow reactor. Total scattering measurements were performed at the 28-ID-2 (XPD) beamline and small-angle X-ray scattering at the 16-ID (LiX) beamline. Nanocrystal structural parameters of interest, including size, size distribution and atomic structure, were extracted from modeling the total scattering data. The results highlight the potential of these beamlines and the measurement protocols described in this study for studying dynamic processes of colloidal nanocrystal synthesis in solution with timescales on the order of seconds.urn:issn:1600-5775text/htmlThe formation of colloidal CsPbX3 perovskite nanocrystal in solution was interrogated with in situ X-ray total scattering/pair distribution function analysis in a flow cell reactor at the XPD 28-ID-2 beamline.2023-09-22PEROVSKITES; NANOCRYSTALS; SMALL-ANGLE X-RAY SCATTERING; X-RAY TOTAL SCATTERING; NUCLEATION; PAIR DISTRIBUTION FUNCTIONIn situ synchrotron X-ray total scattering measurements and analysis of colloidal CsPbX3 nanocrystals during flow synthesisInternational Union of CrystallographyGreenberg, M.W.Lin, C.-H.Chodankar, S.Ghose, S.K.doi:10.1107/S1600577523007300enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/6research papers10921600-5775Journal of Synchrotron Radiation301099November 2023med@iucr.org2023-09-221600-5775A high-throughput big-data orchestration and processing system for the High Energy Photon Source
http://scripts.iucr.org/cgi-bin/paper?fv5163
High-data-throughput and multimodal-acquisition experiments will prevail in next-generation synchrotron beamlines. Orchestrating dataflow pipelines connecting the data acquisition, processing, visualization and storage ends are becoming increasingly complex and essential for enhancing beamline performance. Mamba Data Worker (MDW) has been developed to address the data challenges for the forthcoming High Energy Photon Source (HEPS). It is an important component of the Mamba experimental control and data acquisition software ecosystem, which enables fast data acquisition and transmission, dynamic configuration of data processing pipelines, data multiplex in streaming, and customized data and metadata assembly. This paper presents the architecture and development plan of MDW, outlines the essential technologies involved, and illustrates its current application at the Beijing Synchrotron Radiation Facility (BSRF).textHigh-data-throughput and multimodal-acquisition experiments will prevail in next-generation synchrotron beamlines. Orchestrating dataflow pipelines connecting the data acquisition, processing, visualization and storage ends are becoming increasingly complex and essential for enhancing beamline performance. Mamba Data Worker (MDW) has been developed to address the data challenges for the forthcoming High Energy Photon Source (HEPS). It is an important component of the Mamba experimental control and data acquisition software ecosystem, which enables fast data acquisition and transmission, dynamic configuration of data processing pipelines, data multiplex in streaming, and customized data and metadata assembly. This paper presents the architecture and development plan of MDW, outlines the essential technologies involved, and illustrates its current application at the Beijing Synchrotron Radiation Facility (BSRF).urn:issn:1600-5775text/htmlMamba Data Worker (MDW) has been developed as a high-throughput, multimodal data orchestration and processing system for the High Energy Photon Source (HEPS). It acts as the main artery system for data and metadata in data acquisition, storage and online analysis. The design and future development plans of MDW are discussed.2023-09-20BEAMLINE SOFTWARE; DATA ACQUISITION; DATA MANAGEMENT; HIGH-THROUGHPUT EXPERIMENT; MULTIMODAL EXPERIMENTSA high-throughput big-data orchestration and processing system for the High Energy Photon SourceInternational Union of CrystallographyLi, X.Zhang, Y.Liu, Y.Li, P.Hu, H.Wang, L.He, P.Dong, Y.Zhang, C.doi:10.1107/S1600577523006951enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/6research papers1600-5775November 202330Journal of Synchrotron Radiationmed@iucr.org1600-57752023-09-20Laboratory-based X-ray spectrometer for actinide science
http://scripts.iucr.org/cgi-bin/paper?ye5034
X-ray absorption and emission spectroscopies nowadays are advanced characterization methods for fundamental and applied actinide research. One of the advantages of these methods is to reveal slight changes in the structural and electronic properties of radionuclides. The experiments are generally carried out at synchrotrons. However, considerable progress has been made to construct laboratory-based X-ray spectrometers for X-ray absorption and emission spectroscopies. Laboratory spectrometers are reliable, effective and accessible alternatives to synchrotrons, especially for actinide research, which allow dispensing with high costs of the radioactive sample transport and synchrotron time. Moreover, data from laboratory spectrometers, obtained within a reasonable time, are comparable with synchrotron results. Thereby, laboratory spectrometers can complement synchrotrons or can be used for preliminary experiments to find perspective samples for synchrotron experiments with better resolution. Here, the construction and implementation of an X-ray spectrometer (LomonosovXAS) in Johann-geometry at a radiochemistry laboratory is reported. Examples are given of the application of LomonosovXAS to actinide systems relevant to the chemistry of f-elements, the physical chemistry of nuclear power engineering and the long-term disposal of spent nuclear fuel.textX-ray absorption and emission spectroscopies nowadays are advanced characterization methods for fundamental and applied actinide research. One of the advantages of these methods is to reveal slight changes in the structural and electronic properties of radionuclides. The experiments are generally carried out at synchrotrons. However, considerable progress has been made to construct laboratory-based X-ray spectrometers for X-ray absorption and emission spectroscopies. Laboratory spectrometers are reliable, effective and accessible alternatives to synchrotrons, especially for actinide research, which allow dispensing with high costs of the radioactive sample transport and synchrotron time. Moreover, data from laboratory spectrometers, obtained within a reasonable time, are comparable with synchrotron results. Thereby, laboratory spectrometers can complement synchrotrons or can be used for preliminary experiments to find perspective samples for synchrotron experiments with better resolution. Here, the construction and implementation of an X-ray spectrometer (LomonosovXAS) in Johann-geometry at a radiochemistry laboratory is reported. Examples are given of the application of LomonosovXAS to actinide systems relevant to the chemistry of f-elements, the physical chemistry of nuclear power engineering and the long-term disposal of spent nuclear fuel.urn:issn:1600-5775text/htmlExperiments demonstrate that laboratory X-ray sources possess adequate power for conducting both X-ray absorption spectroscopy and X-ray emission spectroscopy measurements in the examination of actinides. Furthermore, the obtained spectra from these measurements are in agreement with synchrotron data.2023-09-22LABORATORY-BASED; X-RAY SPECTROMETERS; X-RAY ABSORPTION SPECTROSCOPY; X-RAY EMISSION SPECTROSCOPYLaboratory-based X-ray spectrometer for actinide scienceInternational Union of CrystallographyNovichkov, D.Trigub, A.Gerber, E.Nevolin, I.Romanchuk, A.Matveev, P.Kalmykov, S.doi:10.1107/S1600577523006926enhttps://creativecommons.org/licenses/by/4.0/2023-09-221600-5775med@iucr.org30Journal of Synchrotron Radiation1126November 20231600-57751114research papershttps://creativecommons.org/licenses/by/4.0/6Pb speciation and elemental distribution in leeks by micro X-ray fluorescence and X-ray absorption near-edge structure
http://scripts.iucr.org/cgi-bin/paper?ye5033
Vegetables are crucial to a human diet as they supply the body with essential vitamins, minerals, etc. Heavy metals that accumulate in plants consequently enter the food chain and endanger people's health. Studying the spatial distribution and chemical forms of elements in plant/vegetable tissues is vital to comprehending the potential interactions between elements and detoxification mechanisms. In this study, leek plants and soil from vegetable gardens near lead–zinc mines were collected and cultivated with 500 mg L−1 PbNO3 solutions for three weeks. Micro X-ray fluorescence was used to map the distribution of Pb and other chemical elements in leek roots, and X-ray absorption near-edge spectroscopy was used to assess the Pb speciation in leek roots and leaves. These findings demonstrated that Pb, Cu, Mn, Cr, Ti and Fe were detected in the outer rings of the root's cross section, and high-intensity points were observed in the epidermis. Zn, K and Ca, on the other hand, were distributed throughout the root's cross section. Leek root and leaf contained significant quantities of lead phosphate and basic lead carbonate at more than 80%, followed by lead sulfide (19%) and lead stearate (11.1%). The capacity of leek roots to convert ambient lead into precipitated lead and fix it on the root epidermis and other inner surfaces is a key mechanism for reducing the toxic effects of Pb.textVegetables are crucial to a human diet as they supply the body with essential vitamins, minerals, etc. Heavy metals that accumulate in plants consequently enter the food chain and endanger people's health. Studying the spatial distribution and chemical forms of elements in plant/vegetable tissues is vital to comprehending the potential interactions between elements and detoxification mechanisms. In this study, leek plants and soil from vegetable gardens near lead–zinc mines were collected and cultivated with 500 mg L−1 PbNO3 solutions for three weeks. Micro X-ray fluorescence was used to map the distribution of Pb and other chemical elements in leek roots, and X-ray absorption near-edge spectroscopy was used to assess the Pb speciation in leek roots and leaves. These findings demonstrated that Pb, Cu, Mn, Cr, Ti and Fe were detected in the outer rings of the root's cross section, and high-intensity points were observed in the epidermis. Zn, K and Ca, on the other hand, were distributed throughout the root's cross section. Leek root and leaf contained significant quantities of lead phosphate and basic lead carbonate at more than 80%, followed by lead sulfide (19%) and lead stearate (11.1%). The capacity of leek roots to convert ambient lead into precipitated lead and fix it on the root epidermis and other inner surfaces is a key mechanism for reducing the toxic effects of Pb.urn:issn:1600-5775text/htmlLeek roots can physiologically convert about 80% of environmental lead into insoluble lead phosphate and lead carbonate, and leek leaves also contain similar proportions of lead phosphate and lead carbonate. An essential mechanism of Pb detoxification is the development of significant amounts of lead precipitation and immobilization on the root epidermis and other inner surfaces.2023-08-24HEAVY METAL; SPATIAL DISTRIBUTION; SYNCHROTRON RADIATION; XANES; DETOXIFICATION MECHANISMPb speciation and elemental distribution in leeks by micro X-ray fluorescence and X-ray absorption near-edge structureInternational Union of CrystallographySun, J.Yang, Y.Luo, L.doi:10.1107/S1600577523006616enhttps://creativecommons.org/licenses/by/4.0/1600-57755https://creativecommons.org/licenses/by/4.0/934research papersmed@iucr.org1600-57752023-08-24September 202394030Journal of Synchrotron RadiationToward a fully coherent tender and hard X-ray free-electron laser via cascaded EEHG in fourth-generation synchrotron light sources
http://scripts.iucr.org/cgi-bin/paper?yi5139
Free-electron-laser-based beamlines utilize fully coherent laser pulses with extremely narrow bandwidth allowing direct use of X-rays without monochromators. This could be very beneficial for all users of current and future fourth-generation diffraction-limited synchrotron light sources (DL-SLSs) who need narrowband full-coherence high-brightness X-ray pulses. Based on our previous finding, i.e. that separating the two stages of echo-enabled harmonic generation (EEHG) with a few extra bending-magnet sections provides an effective way to increase the momentum compaction of chicane 1, one can simultaneously achieve adequate prebunching at extremely high harmonics as well as keep the energy modulation to the ideal minimum. This could open the door for cascaded EEHG, toward fully coherent tender and hard X-ray wavelengths. Built on our compact design of a twin-pulse seeding electron beam with an adjustable delay and timing jitter at the level of a few femtoseconds, a cascaded EEHG can be implemented, which includes two EEHG beamlines, where the radiation pulse generated by the first beamline with harmonic h1 could be used as the input seed laser pulse to the second beamline with harmonic h2. Hence, the second radiator could potentially reach very high harmonics [h = h1(20)h2(25–100)] from 500 to 2000, corresponding to tender and hard X-ray wavelengths. It is demonstrated that the cascaded EEHG scheme is compatible with almost any current or planned fourth-generation DL-SLS, with significant benefits for space-limited storage rings in particular. The main advantage is that this scheme requires almost no change of the storage-ring lattice and is fully compatible with other beamlines. Current proposals for rings with much longer straight sections would add self-amplified spontaneous emission as another viable option for storage-ring-based free-electron lasers.textFree-electron-laser-based beamlines utilize fully coherent laser pulses with extremely narrow bandwidth allowing direct use of X-rays without monochromators. This could be very beneficial for all users of current and future fourth-generation diffraction-limited synchrotron light sources (DL-SLSs) who need narrowband full-coherence high-brightness X-ray pulses. Based on our previous finding, i.e. that separating the two stages of echo-enabled harmonic generation (EEHG) with a few extra bending-magnet sections provides an effective way to increase the momentum compaction of chicane 1, one can simultaneously achieve adequate prebunching at extremely high harmonics as well as keep the energy modulation to the ideal minimum. This could open the door for cascaded EEHG, toward fully coherent tender and hard X-ray wavelengths. Built on our compact design of a twin-pulse seeding electron beam with an adjustable delay and timing jitter at the level of a few femtoseconds, a cascaded EEHG can be implemented, which includes two EEHG beamlines, where the radiation pulse generated by the first beamline with harmonic h1 could be used as the input seed laser pulse to the second beamline with harmonic h2. Hence, the second radiator could potentially reach very high harmonics [h = h1(20)h2(25–100)] from 500 to 2000, corresponding to tender and hard X-ray wavelengths. It is demonstrated that the cascaded EEHG scheme is compatible with almost any current or planned fourth-generation DL-SLS, with significant benefits for space-limited storage rings in particular. The main advantage is that this scheme requires almost no change of the storage-ring lattice and is fully compatible with other beamlines. Current proposals for rings with much longer straight sections would add self-amplified spontaneous emission as another viable option for storage-ring-based free-electron lasers.urn:issn:1600-5775text/htmlBuilt on our compact design of a twin-pulse seeding electron beam with an adjustable delay and a few femtoseconds timing jitter, a storage-ring-based cascaded EEHG can be implemented, which consists of two EEHG beamlines, where the radiation pulse generated by the first beamline could be used as the input seed laser pulse to the second beamline. Hence, the second radiator could potentially reach very high harmonics, toward fully coherent tender and hard X-ray wavelengths.2023-08-24STORAGE-RING-BASED FREE-ELECTRON LASERS; CASCADED ECHO-ENABLED HARMONIC GENERATION; DIFFRACTION-LIMITED SYNCHROTRON LIGHT SOURCES; COHERENT RADIATION; SASE AND XFEL OSCILLATORSToward a fully coherent tender and hard X-ray free-electron laser via cascaded EEHG in fourth-generation synchrotron light sourcesInternational Union of CrystallographyYang, X.Yu, L.H.Smaluk, V.Shaftan, T.Huang, X.doi:10.1107/S1600577523006586enhttps://creativecommons.org/licenses/by/4.0/5https://creativecommons.org/licenses/by/4.0/research papers8611600-5775875Journal of Synchrotron Radiation30September 2023med@iucr.org2023-08-241600-5775Mutual optical intensity propagation through non-ideal two-dimensional mirrors
http://scripts.iucr.org/cgi-bin/paper?mo5268
The mutual optical intensity (MOI) model is a partially coherent radiation propagation tool that can sequentially simulate beamline optics and provide beam intensity, local degree of coherence and phase distribution at any location along a beamline. This paper extends the MOI model to non-ideal two-dimensional (2D) optical systems, such as ellipsoidal and toroidal mirrors with 2D figure errors. Simulation results show that one can tune the trade-off between calculation efficiency and accuracy by varying the number of wavefront elements. The focal spot size of an ellipsoidal mirror calculated with 100 × 100 elements gives less than 0.4% deviation from that with 250 × 250 elements, and the computation speed is nearly two orders of magnitude faster. Effects of figure errors on 2D focusing are also demonstrated for a non-ideal ellipsoidal mirror and by comparing the toroidal and ellipsoidal mirrors. Finally, the MOI model is benchmarked against the multi-electron Synchrotron Radiation Workshop (SRW) code showing the model's high accuracy.textThe mutual optical intensity (MOI) model is a partially coherent radiation propagation tool that can sequentially simulate beamline optics and provide beam intensity, local degree of coherence and phase distribution at any location along a beamline. This paper extends the MOI model to non-ideal two-dimensional (2D) optical systems, such as ellipsoidal and toroidal mirrors with 2D figure errors. Simulation results show that one can tune the trade-off between calculation efficiency and accuracy by varying the number of wavefront elements. The focal spot size of an ellipsoidal mirror calculated with 100 × 100 elements gives less than 0.4% deviation from that with 250 × 250 elements, and the computation speed is nearly two orders of magnitude faster. Effects of figure errors on 2D focusing are also demonstrated for a non-ideal ellipsoidal mirror and by comparing the toroidal and ellipsoidal mirrors. Finally, the MOI model is benchmarked against the multi-electron Synchrotron Radiation Workshop (SRW) code showing the model's high accuracy.urn:issn:1600-5775text/htmlMutual optical intensity propagation through non-ideal two-dimensional mirrors is realized by combining geometric ray-tracing and wavefront propagation.2023-08-23SYNCHROTRON BEAMLINE; PARTIALLY COHERENT LIGHT; MUTUAL OPTICAL INTENSITY; TWO-DIMENSIONAL MIRRORSMutual optical intensity propagation through non-ideal two-dimensional mirrorsInternational Union of CrystallographyMeng, X.Wang, Y.Shi, X.Ren, J.Sun, W.Cao, J.Li, J.Tai, R.doi:10.1107/S1600577523006343enhttps://creativecommons.org/licenses/by/4.0/30Journal of Synchrotron Radiation909September 20232023-08-231600-5775med@iucr.org902research papershttps://creativecommons.org/licenses/by/4.0/51600-5775Exploring beam size measurement based on the Talbot effect at BEPCII
http://scripts.iucr.org/cgi-bin/paper?mo5271
Vertical beam size measurements were carried out at Beijing Electron–Positron Collider II (BEPCII) using a phase grating and an absorption grating based on the Talbot effect. The transverse coherence of synchrotron radiation is closely related to beam size. Due to the partial coherence of the synchrotron radiation source, the coherence length can be calculated by measuring the visibility decay of interferograms recorded at different distances behind the gratings. A vertical beam size of 68.19 ± 2 µm was obtained based on the relationship between the coherence length and beam size at the 3W1 beamline of BEPCII. A comparison of the vertical emittance derived from the grating Talbot method and the synchrotron radiation visible light interferometer method was presented. The vertical emittances from the two methods are 1.41 nm rad and 1.40 nm rad, respectively. The 0.1% difference indicates that the grating Talbot method for beam size measurement is reliable. This technique has great potential for small beam size measurement of fourth-generation synchrotron radiation light sources, considering its small diffraction limitation and simple experimental setups.textVertical beam size measurements were carried out at Beijing Electron–Positron Collider II (BEPCII) using a phase grating and an absorption grating based on the Talbot effect. The transverse coherence of synchrotron radiation is closely related to beam size. Due to the partial coherence of the synchrotron radiation source, the coherence length can be calculated by measuring the visibility decay of interferograms recorded at different distances behind the gratings. A vertical beam size of 68.19 ± 2 µm was obtained based on the relationship between the coherence length and beam size at the 3W1 beamline of BEPCII. A comparison of the vertical emittance derived from the grating Talbot method and the synchrotron radiation visible light interferometer method was presented. The vertical emittances from the two methods are 1.41 nm rad and 1.40 nm rad, respectively. The 0.1% difference indicates that the grating Talbot method for beam size measurement is reliable. This technique has great potential for small beam size measurement of fourth-generation synchrotron radiation light sources, considering its small diffraction limitation and simple experimental setups.urn:issn:1600-5775text/htmlA method based on the Talbot effect for accurate beam size measurement has been implemented at Beijing Electron–Positron Collider II. This technique has great prospects for application in small beam size measurement of fourth-generation synchrotron light sources, benefiting from its small diffraction limitation.2023-08-23TALBOT EFFECT; INTERFEROGRAMS VISIBILITY; COHERENCE LENGTH; BEAM SIZE MEASUREMENT; SYNCHROTRON RADIATION LIGHT SOURCEExploring beam size measurement based on the Talbot effect at BEPCIIInternational Union of CrystallographyZhang, W.Zhu, D.Sui, Y.Yue, J.Cao, J.He, J.doi:10.1107/S1600577523006355enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/5910research papersmed@iucr.org1600-57752023-08-23September 2023Journal of Synchrotron Radiation30916BL09XU: an advanced hard X-ray photoelectron spectroscopy beamline of SPring-8
http://scripts.iucr.org/cgi-bin/paper?ok5097
The BL09XU beamline of SPring-8 has been reorganized into a beamline dedicated for hard X-ray photoelectron spectroscopy (HAXPES) to provide advanced capabilities with upgraded optical instruments. The beamline has two HAXPES analyzers to cover a wide range of applications. Two sets of double channel-cut crystal monochromators with the Si(220) and (311) reflections were installed to perform resonant HAXPES analyses with a total energy resolution of less than 300 meV over a wide energy range (4.9–12 keV) while achieving a fixed-exit condition. A double-crystal X-ray phase retarder using diamond crystals controls the polarization state with a high degree of polarization over 0.9 in the wide energy range 5.9–9.5 keV. Each HAXPES analyzer is equipped with a focusing mirror to provide a high-flux microbeam. The design and performance of the upgraded instruments are presented.textThe BL09XU beamline of SPring-8 has been reorganized into a beamline dedicated for hard X-ray photoelectron spectroscopy (HAXPES) to provide advanced capabilities with upgraded optical instruments. The beamline has two HAXPES analyzers to cover a wide range of applications. Two sets of double channel-cut crystal monochromators with the Si(220) and (311) reflections were installed to perform resonant HAXPES analyses with a total energy resolution of less than 300 meV over a wide energy range (4.9–12 keV) while achieving a fixed-exit condition. A double-crystal X-ray phase retarder using diamond crystals controls the polarization state with a high degree of polarization over 0.9 in the wide energy range 5.9–9.5 keV. Each HAXPES analyzer is equipped with a focusing mirror to provide a high-flux microbeam. The design and performance of the upgraded instruments are presented.urn:issn:1600-5775text/htmlThe BL09XU beamline of SPring-8 has been upgraded to a beamline dedicated for hard X-ray photoelectron spectroscopy to provide advanced capabilities with improved optical instruments.2023-08-23HARD X-RAY PHOTOELECTRON SPECTROSCOPY; HAXPES; BEAMLINES; X-RAY OPTICS; HIGH-FLUX MICROBEAMS; DOUBLE-CRYSTAL X-RAY PHASE RETARDERSBL09XU: an advanced hard X-ray photoelectron spectroscopy beamline of SPring-8International Union of CrystallographyYasui, A.Takagi, Y.Osaka, T.Senba, Y.Yamazaki, H.Koyama, T.Yumoto, H.Ohashi, H.Motomura, K.Nakajima, K.Sugahara, M.Kawamura, N.Tamasaku, K.Tamenori, Y.Yabashi, M.doi:10.1107/S160057752300629Xenhttps://creativecommons.org/licenses/by/4.0/beamlines10135https://creativecommons.org/licenses/by/4.0/1600-5775102230Journal of Synchrotron RadiationSeptember 20232023-08-231600-5775med@iucr.orgDevelopment of a versatile electrochemical cell for in situ grazing-incidence X-ray diffraction during non-aqueous electrochemical nitrogen reduction
http://scripts.iucr.org/cgi-bin/paper?vy5012
In situ techniques are essential to understanding the behavior of electrocatalysts under operating conditions. When employed, in situ synchrotron grazing-incidence X-ray diffraction (GI-XRD) can provide time-resolved structural information of materials formed at the electrode surface. In situ cells, however, often require epoxy resins to secure electrodes, do not enable electrolyte flow, or exhibit limited chemical compatibility, hindering the study of non-aqueous electrochemical systems. Here, a versatile electrochemical cell for air-free in situ synchrotron GI-XRD during non-aqueous Li-mediated electrochemical N2 reduction (Li-N2R) has been designed. This cell not only fulfills the stringent material requirements necessary to study this system but is also readily extendable to other electrochemical systems. Under conditions relevant to non-aqueous Li-N2R, the formation of Li metal, LiOH and Li2O as well as a peak consistent with the α-phase of Li3N was observed, thus demonstrating the functionality of this cell toward developing a mechanistic understanding of complicated electrochemical systems.textIn situ techniques are essential to understanding the behavior of electrocatalysts under operating conditions. When employed, in situ synchrotron grazing-incidence X-ray diffraction (GI-XRD) can provide time-resolved structural information of materials formed at the electrode surface. In situ cells, however, often require epoxy resins to secure electrodes, do not enable electrolyte flow, or exhibit limited chemical compatibility, hindering the study of non-aqueous electrochemical systems. Here, a versatile electrochemical cell for air-free in situ synchrotron GI-XRD during non-aqueous Li-mediated electrochemical N2 reduction (Li-N2R) has been designed. This cell not only fulfills the stringent material requirements necessary to study this system but is also readily extendable to other electrochemical systems. Under conditions relevant to non-aqueous Li-N2R, the formation of Li metal, LiOH and Li2O as well as a peak consistent with the α-phase of Li3N was observed, thus demonstrating the functionality of this cell toward developing a mechanistic understanding of complicated electrochemical systems.urn:issn:1600-5775text/htmlA new electrochemical cell design enables air-free in situ synchrotron grazing-incidence X-ray diffraction measurements of Li-containing species during non-aqueous Li-mediated electrochemical nitrogen reduction. Such measurements will facilitate the development of a mechanistic understanding of the electrode–electrolyte interface under Li-N2R conditions, allowing for the rational design of Li-N2R toward improved Faradaic efficiency toward NH3.2023-08-18NON-AQUEOUS LI-MEDIATED ELECTROCHEMICAL NITROGEN REDUCTION; SYNCHROTRON X-RAY DIFFRACTION; ELECTROCATALYSIS; ELECTROCHEMICAL CELL DESIGN; GRAZING INCIDENCE; IN SITU; SOLID ELECTROLYTE INTERPHASEDevelopment of a versatile electrochemical cell for in situ grazing-incidence X-ray diffraction during non-aqueous electrochemical nitrogen reductionInternational Union of CrystallographyBlair, S.J.Nielander, A.C.Stone, K.H.Kreider, M.E.Niemann, V.A.Benedek, P.McShane, E.J.Gallo, A.Jaramillo, T.F.doi:10.1107/S1600577523006331enhttps://creativecommons.org/licenses/by/4.0/1600-5775https://creativecommons.org/licenses/by/4.0/5917research papersmed@iucr.org1600-57752023-08-18September 202330Journal of Synchrotron Radiation922Silicon-nitride-based entrance slit design for the high-power-density monochromator in TPS 45A
http://scripts.iucr.org/cgi-bin/paper?ve5170
Details of the design and operational status of the silicon-nitride-based entrance slit installed in the Taiwan Photon Source (TPS) 45A beamline are given. The slit is a diamond blade edge etched onto a copper slit part, which is in thermal contact with the silicon nitride base. A stable slit opening smaller than 4 µm is achieved in TPS 45A. The beam size at the slit has a full width at half-maximum of 3 µm in the vertical direction with a power of 20 W. Additionally, a hard stop made of invar is incorporated to control the thermal expansion displacement. The slit reduces the size and increases the stability of the source of the monochromator. Consequently, a higher energy resolution and excellent beamline stability are achieved.textDetails of the design and operational status of the silicon-nitride-based entrance slit installed in the Taiwan Photon Source (TPS) 45A beamline are given. The slit is a diamond blade edge etched onto a copper slit part, which is in thermal contact with the silicon nitride base. A stable slit opening smaller than 4 µm is achieved in TPS 45A. The beam size at the slit has a full width at half-maximum of 3 µm in the vertical direction with a power of 20 W. Additionally, a hard stop made of invar is incorporated to control the thermal expansion displacement. The slit reduces the size and increases the stability of the source of the monochromator. Consequently, a higher energy resolution and excellent beamline stability are achieved.urn:issn:1600-5775text/htmlDetails of the design and operational status of the silicon-nitride-based entrance slit installed in the Taiwan Photon Source 45A beamline are given.2023-08-18MONOCHROMATOR; ENTRANCE SLIT; SILICON NITRIDE; STABILITYSilicon-nitride-based entrance slit design for the high-power-density monochromator in TPS 45AInternational Union of CrystallographyHsu, M.-Y.Fu, H.-W.Fung, H.-S.Hua, C.-Y.Huang, L.-J.Tsai, H.-M.doi:10.1107/S1600577523006240enhttps://creativecommons.org/licenses/by/4.0/research papers8955https://creativecommons.org/licenses/by/4.0/1600-5775September 2023901Journal of Synchrotron Radiation301600-57752023-08-18med@iucr.orgCatMass: software for calculating optimal sample masses for X-ray absorption spectroscopy experiments involving complex sample compositions
http://scripts.iucr.org/cgi-bin/paper?rv5174
This paper presents software for calculating the optimal mass of samples with complex compositions (e.g. supported metal catalysts) for X-ray absorption spectroscopy (XAS) and scattering measurements. The ability to calculate the sample mass and other relevant parameters needed for an XAS measurement allows experimentalists to be better prepared in terms of detector selection, energy range of scan and overall time needed to complete the measurement, thus increasing efficiency. CatMass builds on existing sample mass calculators allowing users to determine the optimum sample preparation, collection geometry, usable energy range for a scan and approximate edge step of the absorption event. Visualization tools present the absorption calculation results in a format familiar to XAS experimentalists, with the added ability to save calculations and plots for future reference or recalculation. CatMass is a program broadly applicable in catalysis and is helpful for users with complex samples due to composition/stoichiometry or multiple competing elements.textThis paper presents software for calculating the optimal mass of samples with complex compositions (e.g. supported metal catalysts) for X-ray absorption spectroscopy (XAS) and scattering measurements. The ability to calculate the sample mass and other relevant parameters needed for an XAS measurement allows experimentalists to be better prepared in terms of detector selection, energy range of scan and overall time needed to complete the measurement, thus increasing efficiency. CatMass builds on existing sample mass calculators allowing users to determine the optimum sample preparation, collection geometry, usable energy range for a scan and approximate edge step of the absorption event. Visualization tools present the absorption calculation results in a format familiar to XAS experimentalists, with the added ability to save calculations and plots for future reference or recalculation. CatMass is a program broadly applicable in catalysis and is helpful for users with complex samples due to composition/stoichiometry or multiple competing elements.urn:issn:1600-5775text/htmlCatMass is a new software for calculating the optimal sample mass of samples with complex compositions (e.g. a supported metal catalyst mixed with a diluent) for X-ray absorption and X-ray scattering experiments with supplemental results to guide experimental design and collection geometry.2023-08-18CATMASS; XAS; CATALYSTS; SAMPLE PREPARATION OPTIMIZATIONCatMass: software for calculating optimal sample masses for X-ray absorption spectroscopy experiments involving complex sample compositionsInternational Union of CrystallographyPerez-Aguilar, J.E.Caine, A.Bare, S.R.Hoffman, A.S.doi:10.1107/S160057752300615Xenhttps://creativecommons.org/licenses/by/4.0/1023computer programshttps://creativecommons.org/licenses/by/4.0/51600-5775September 202330Journal of Synchrotron Radiation10291600-57752023-08-18med@iucr.orgInversion model for extracting chemically resolved depth profiles across liquid interfaces of various configurations from XPS data: PROPHESY
http://scripts.iucr.org/cgi-bin/paper?ok5094
PROPHESY, a technique for the reconstruction of surface-depth profiles from X-ray photoelectron spectroscopy data, is introduced. The inversion methodology is based on a Bayesian framework and primal-dual convex optimization. The acquisition model is developed for several geometries representing different sample types: plane (bulk sample), cylinder (liquid microjet) and sphere (droplet). The methodology is tested and characterized with respect to simulated data as a proof of concept. Possible limitations of the method due to uncertainty in the attenuation length of the photo-emitted electron are illustrated.textPROPHESY, a technique for the reconstruction of surface-depth profiles from X-ray photoelectron spectroscopy data, is introduced. The inversion methodology is based on a Bayesian framework and primal-dual convex optimization. The acquisition model is developed for several geometries representing different sample types: plane (bulk sample), cylinder (liquid microjet) and sphere (droplet). The methodology is tested and characterized with respect to simulated data as a proof of concept. Possible limitations of the method due to uncertainty in the attenuation length of the photo-emitted electron are illustrated.urn:issn:1600-5775text/htmlThe PROPHESY framework for obtaining absolute depth profiles from discrete X-ray photoelectron spectra is introduced. It is composed of (i) a model for an X-ray photoelectron spectroscopy experiment accounting for sample geometry, and (ii) an inversion model to reconstruct the concentration profile at the surface of a liquid sample. As a proof of concept, it is applied to simulated data.2023-08-23X-RAY PHOTOELECTRON SPECTROSCOPY; DEPTH PROFILE; INVERSION ALGORITHM; ATMOSPHERIC SURFACES; ACQUISITION MODELInversion model for extracting chemically resolved depth profiles across liquid interfaces of various configurations from XPS data: PROPHESYInternational Union of CrystallographyOzon, M.Tumashevich, K.Lin, J.J.Prisle, N.L.doi:10.1107/S1600577523006124enhttps://creativecommons.org/licenses/by/4.0/2023-08-231600-5775med@iucr.orgJournal of Synchrotron Radiation30961September 20231600-5775research papers941https://creativecommons.org/licenses/by/4.0/5Improved precision in As speciation analysis with HERFD-XANES at the As K-edge: the case of As speciation in mine waste. Corrigendum
http://scripts.iucr.org/cgi-bin/paper?ye9018
The name of an author in the article by Saurette et al. (2022) [J. Synchrotron Rad. 29, 1198–1208] is corrected.textThe name of an author in the article by Saurette et al. (2022) [J. Synchrotron Rad. 29, 1198–1208] is corrected.urn:issn:1600-5775text/htmlCorrigendum to the article by Saurette et al. (2022) [J. Synchrotron Rad. 29, 1198–1208].2023-10-18HERFD-XANES; GEOCHEMISTRY; MINE WASTE; ARSENIC; LINEAR COMBINATION FITTINGImproved precision in As speciation analysis with HERFD-XANES at the As K-edge: the case of As speciation in mine waste. CorrigendumInternational Union of CrystallographySaurette, E.M.Finfrock, Y.Z.Verbuyst, B.Blowes, D.W.McBeth, J.M.Ptacek, C.J.doi:10.1107/S1600577523006069enhttps://creativecommons.org/licenses/by/4.0/1600-57752023-10-18med@iucr.orgNovember 2023Journal of Synchrotron Radiation3011831600-5775addenda and errata1183https://creativecommons.org/licenses/by/4.0/6Fast, automated, continuous energy scans for experimental phasing at the BioMAX beamline
http://scripts.iucr.org/cgi-bin/paper?wz5032
In X-ray macromolecular crystallography (MX), single-wavelength anomalous dispersion (SAD) and multi-wavelength anomalous dispersion (MAD) techniques are commonly used for obtaining experimental phases. For an MX synchrotron beamline to support SAD and MAD techniques it is a prerequisite to have a reliable, fast and well automated energy scan routine. This work reports on a continuous energy scan procedure newly implemented at the BioMAX MX beamline at MAX IV Laboratory. The continuous energy scan is fully automated, capable of measuring accurate fluorescence counts over the absorption edge of interest while minimizing the sample exposure to X-rays, and is about a factor of five faster compared with a conventional step scan previously operational at BioMAX. The implementation of the continuous energy scan facilitates the prompt access to the anomalous scattering data, required for the SAD and MAD experiments.textIn X-ray macromolecular crystallography (MX), single-wavelength anomalous dispersion (SAD) and multi-wavelength anomalous dispersion (MAD) techniques are commonly used for obtaining experimental phases. For an MX synchrotron beamline to support SAD and MAD techniques it is a prerequisite to have a reliable, fast and well automated energy scan routine. This work reports on a continuous energy scan procedure newly implemented at the BioMAX MX beamline at MAX IV Laboratory. The continuous energy scan is fully automated, capable of measuring accurate fluorescence counts over the absorption edge of interest while minimizing the sample exposure to X-rays, and is about a factor of five faster compared with a conventional step scan previously operational at BioMAX. The implementation of the continuous energy scan facilitates the prompt access to the anomalous scattering data, required for the SAD and MAD experiments.urn:issn:1600-5775text/htmlA novel continuous energy scan routine has been implemented at the BioMAX beamline at MAX IV Laboratory. It is about five times faster than the conventional step scanning routine and facilitates user experiments utilizing the single-wavelength anomalous dispersion and multi-wavelength anomalous dispersion techniques.2023-08-01MX BEAMLINE; MAD SAD PHASING; CONTINUOUS ENERGY SCAN; FLYING SCAN; MOTION SYNCHRONIZATIONFast, automated, continuous energy scans for experimental phasing at the BioMAX beamlineInternational Union of CrystallographyGorgisyan, I.Bell, P.Cascella, M.Eguiraun, M.Freitas, Á.Lidon-Simon, J.Nan, J.Takahashi, C.Tarawneh, H.Ursby, T.Gonzalez, A.doi:10.1107/S1600577523005738enhttps://creativecommons.org/licenses/by/4.0/885research papershttps://creativecommons.org/licenses/by/4.0/51600-5775September 202330Journal of Synchrotron Radiation8941600-57752023-08-01med@iucr.orgA hybrid machine-learning approach for analysis of methane hydrate formation dynamics in porous media with synchrotron CT imaging
http://scripts.iucr.org/cgi-bin/paper?gy5046
Fast multi-phase processes in methane hydrate bearing samples pose a challenge for quantitative micro-computed tomography study and experiment steering due to complex tomographic data analysis involving time-consuming segmentation procedures. This is because of the sample's multi-scale structure, which changes over time, low contrast between solid and fluid materials, and the large amount of data acquired during dynamic processes. Here, a hybrid approach is proposed for the automatic segmentation of tomographic data from time-resolved imaging of methane gas-hydrate formation in sandy granular media, which includes a deep-learning 3D U-Net model. To prepare a training dataset for the 3D U-Net, a technique to automate data labeling based on sample-specific information about the mineral matrix immobility and occasional fluid movement in pores is proposed. Automatic segmentation allowed for studying properties of the hydrate growth in pores, as well as dynamic processes such as incremental flow and redistribution of pore brine. Results of the quantitative analysis showed that for typical gas-hydrate stability parameters (100 bar methane pressure, 7°C temperature) the rate of formation is slow (less than 1% per hour), after which the surface area of contact between brine and gas increases, resulting in faster formation (2.5% per hour). Hydrate growth reaches the saturation point after 11 h of the experiment. Finally, the efficacy of the proposed segmentation scheme in on-the-fly automatic data analysis and experiment steering with zooming to regions of interest is demonstrated.textFast multi-phase processes in methane hydrate bearing samples pose a challenge for quantitative micro-computed tomography study and experiment steering due to complex tomographic data analysis involving time-consuming segmentation procedures. This is because of the sample's multi-scale structure, which changes over time, low contrast between solid and fluid materials, and the large amount of data acquired during dynamic processes. Here, a hybrid approach is proposed for the automatic segmentation of tomographic data from time-resolved imaging of methane gas-hydrate formation in sandy granular media, which includes a deep-learning 3D U-Net model. To prepare a training dataset for the 3D U-Net, a technique to automate data labeling based on sample-specific information about the mineral matrix immobility and occasional fluid movement in pores is proposed. Automatic segmentation allowed for studying properties of the hydrate growth in pores, as well as dynamic processes such as incremental flow and redistribution of pore brine. Results of the quantitative analysis showed that for typical gas-hydrate stability parameters (100 bar methane pressure, 7°C temperature) the rate of formation is slow (less than 1% per hour), after which the surface area of contact between brine and gas increases, resulting in faster formation (2.5% per hour). Hydrate growth reaches the saturation point after 11 h of the experiment. Finally, the efficacy of the proposed segmentation scheme in on-the-fly automatic data analysis and experiment steering with zooming to regions of interest is demonstrated.urn:issn:1600-5775text/htmlA new hybrid machine-learning approach for the automatic segmentation of dynamic computed tomography images during methane hydrate formation in sandy samples is presented. The algorithm allows for accurate and fast segmentation of gas hydrate changes and fluid flow in the low-contrast environment that is the main step to perform automatic quantitative analysis of processes in hydrate-bearing samples.2023-07-19HYBRID MACHINE-LEARNING SEGMENTATION; X-RAY MICRO-COMPUTED TOMOGRAPHY; IMAGE QUANTITATIVE ANALYSIS; GAS HYDRATESA hybrid machine-learning approach for analysis of methane hydrate formation dynamics in porous media with synchrotron CT imagingInternational Union of CrystallographyFokin, M.I.Nikitin, V.V.Duchkov, A.A.doi:10.1107/S1600577523005635enhttps://creativecommons.org/licenses/by/4.0/98830Journal of Synchrotron RadiationSeptember 2023med@iucr.org2023-07-191600-57755https://creativecommons.org/licenses/by/4.0/research papers9781600-5775A direct experimental comparison of single-crystal CVD diamond and silicon carbide X-ray beam position monitors
http://scripts.iucr.org/cgi-bin/paper?gy5048
Single-crystal chemical vapour deposition (CVD) diamond detectors are an established transmissive synchrotron beamline diagnostic instrument used for beam position and beam intensity monitoring. A recently commercialized alternative is silicon carbide (4H-SiC) devices. These have the potential to provide the same diagnostic information as commercially available single-crystal CVD diamond X-ray beam position monitors, but with a much larger transmissive aperture. At Diamond Light Source an experimental comparison of the performance of single-crystal CVD diamond and 4H-SiC X-ray beam position monitors has been carried out. A quantitative comparison of their performance is presented in this paper. The single-crystal diamond and 4H-SiC beam position monitors were installed in-line along the synchrotron X-ray beam path enabling synchronous measurements at kilohertz rates of the beam motion from both devices. The results of several tests of the two position monitors' performance are presented: comparing signal uniformity across the surface of the detectors, comparing kHz intensity measurements, and comparing kHz beam position measurements from the detectors. Each test is performed with a range of applied external bias voltages. A discussion of the benefits and limitations of 4H-SiC and single-crystal CVD diamond detectors is included.textSingle-crystal chemical vapour deposition (CVD) diamond detectors are an established transmissive synchrotron beamline diagnostic instrument used for beam position and beam intensity monitoring. A recently commercialized alternative is silicon carbide (4H-SiC) devices. These have the potential to provide the same diagnostic information as commercially available single-crystal CVD diamond X-ray beam position monitors, but with a much larger transmissive aperture. At Diamond Light Source an experimental comparison of the performance of single-crystal CVD diamond and 4H-SiC X-ray beam position monitors has been carried out. A quantitative comparison of their performance is presented in this paper. The single-crystal diamond and 4H-SiC beam position monitors were installed in-line along the synchrotron X-ray beam path enabling synchronous measurements at kilohertz rates of the beam motion from both devices. The results of several tests of the two position monitors' performance are presented: comparing signal uniformity across the surface of the detectors, comparing kHz intensity measurements, and comparing kHz beam position measurements from the detectors. Each test is performed with a range of applied external bias voltages. A discussion of the benefits and limitations of 4H-SiC and single-crystal CVD diamond detectors is included.urn:issn:1600-5775text/htmlAn experimental comparison between 4H-SiC and single-crystal diamond X-ray beam position monitors as synchrotron light sources is given.2023-07-18XBPM; DIAGNOSTICS; DIAMOND; SILICON CARBIDEA direct experimental comparison of single-crystal CVD diamond and silicon carbide X-ray beam position monitorsInternational Union of CrystallographyHoughton, C.Bloomer, C.Bobb, L.doi:10.1107/S1600577523005623enhttps://creativecommons.org/licenses/by/4.0/September 2023Journal of Synchrotron Radiation30med@iucr.org1600-57752023-07-185https://creativecommons.org/licenses/by/4.0/research papers1600-5775The AXEAP2 program for Kβ X-ray emission spectra analysis using artificial intelligence
http://scripts.iucr.org/cgi-bin/paper?ok5093
The processing and analysis of synchrotron data can be a complex task, requiring specialized expertise and knowledge. Our previous work addressed the challenge of X-ray emission spectrum (XES) data processing by developing a standalone application using unsupervised machine learning. However, the task of analyzing the processed spectra remains another challenge. Although the non-resonant Kβ XES of 3d transition metals are known to provide electronic structure information such as oxidation and spin state, finding appropriate parameters to match experimental data is a time-consuming and labor-intensive process. Here, a new XES data analysis method based on the genetic algorithm is demonstrated, applying it to Mn, Co and Ni oxides. This approach is also implemented as a standalone application, Argonne X-ray Emission Analysis 2 (AXEAP2), which finds a set of parameters that result in a high-quality fit of the experimental spectrum with minimal intervention. AXEAP2 is able to find a set of parameters that reproduce the experimental spectrum, and provide insights into the 3d electron spin state, 3d–3p electron exchange force and Kβ emission core-hole lifetime.textThe processing and analysis of synchrotron data can be a complex task, requiring specialized expertise and knowledge. Our previous work addressed the challenge of X-ray emission spectrum (XES) data processing by developing a standalone application using unsupervised machine learning. However, the task of analyzing the processed spectra remains another challenge. Although the non-resonant Kβ XES of 3d transition metals are known to provide electronic structure information such as oxidation and spin state, finding appropriate parameters to match experimental data is a time-consuming and labor-intensive process. Here, a new XES data analysis method based on the genetic algorithm is demonstrated, applying it to Mn, Co and Ni oxides. This approach is also implemented as a standalone application, Argonne X-ray Emission Analysis 2 (AXEAP2), which finds a set of parameters that result in a high-quality fit of the experimental spectrum with minimal intervention. AXEAP2 is able to find a set of parameters that reproduce the experimental spectrum, and provide insights into the 3d electron spin state, 3d–3p electron exchange force and Kβ emission core-hole lifetime.urn:issn:1600-5775text/htmlA methodology for analyzing 3d transition metal XES and a user-friendly program named AXEAP2 are presented.2023-08-01AXEAP; XES; ELECTRON INTERACTION; GENETIC ALGORITHM; SPIN STATEThe AXEAP2 program for Kβ X-ray emission spectra analysis using artificial intelligenceInternational Union of CrystallographyHwang, I.-H.Kelly, S.D.Chan, M.K.Y.Stavitski, E.Heald, S.M.Han, S.-W.Schwarz, N.Sun, C.-J.doi:10.1107/S1600577523005684enhttps://creativecommons.org/licenses/by/4.0/933Journal of Synchrotron Radiation30September 20232023-08-011600-5775med@iucr.org923research papers5https://creativecommons.org/licenses/by/4.0/1600-5775Deformation of two-phase aggregates with in situ X-ray tomography in rotating Paris–Edinburgh cell at GPa pressures and high temperature
http://scripts.iucr.org/cgi-bin/paper?vl5010
High-pressure (>1 GPa) torsion apparatus can be coupled with in situ X-ray tomography (XRT) to study microstructures in materials associated with large shear strains. Here, deformation experiments were carried out on multi-phase aggregates at ∼3–5 GPa and ∼300–500°C, using a rotational tomography Paris–Edinburgh press (RoToPEc) with in situ absorption contrast XRT on the PSICHE beamline at Synchrotron SOLEIL. The actual shear strain reached in the samples was quantified with respect to the anvil twisting angles, which is γ ≤ 1 at 90° anvil twist and reaches γ ≃ 5 at 225° anvil twist. 2D and 3D quantifications based on XRT that can be used to study in situ the deformation microfabrics of two-phase aggregates at high shear strain are explored. The current limitations for investigation in real time of deformation microstructures using coupled synchrotron XRT with the RoToPEc are outlined.textHigh-pressure (>1 GPa) torsion apparatus can be coupled with in situ X-ray tomography (XRT) to study microstructures in materials associated with large shear strains. Here, deformation experiments were carried out on multi-phase aggregates at ∼3–5 GPa and ∼300–500°C, using a rotational tomography Paris–Edinburgh press (RoToPEc) with in situ absorption contrast XRT on the PSICHE beamline at Synchrotron SOLEIL. The actual shear strain reached in the samples was quantified with respect to the anvil twisting angles, which is γ ≤ 1 at 90° anvil twist and reaches γ ≃ 5 at 225° anvil twist. 2D and 3D quantifications based on XRT that can be used to study in situ the deformation microfabrics of two-phase aggregates at high shear strain are explored. The current limitations for investigation in real time of deformation microstructures using coupled synchrotron XRT with the RoToPEc are outlined.urn:issn:1600-5775text/htmlThe use of a high-pressure torsion apparatus to deform multi-phase aggregates under high shear strain is explored, and in situ X-ray tomography data at high pressure and high temperature are collected. Step-by-step procedures on strain measurements and image processing are outlined, and results on the studied materials are presented in 2D and 3D.2023-07-19HIGH PRESSURE; IN SITU X-RAY TOMOGRAPHY; DEFORMATION; TWO-PHASE AGGREGATESDeformation of two-phase aggregates with in situ X-ray tomography in rotating Paris–Edinburgh cell at GPa pressures and high temperatureInternational Union of CrystallographyMandolini, T.Chantel, J.Merkel, S.Le Godec, Y.Guignot, N.King, A.Hosdez, J.Henry, L.Hilairet, N.doi:10.1107/S1600577523005374enhttps://creativecommons.org/licenses/by/4.0/1600-57755https://creativecommons.org/licenses/by/4.0/962research papersmed@iucr.org1600-57752023-07-19September 2023977Journal of Synchrotron Radiation30Structural properties in ruptured mitral chordae tendineae measured by synchrotron-based X-ray phase computed tomography
http://scripts.iucr.org/cgi-bin/paper?yi5137
The link between the structural properties and the rupturing of chordae tendineae in the mitral valve complex is still unclear. Synchrotron-radiation-based X-ray phase computed tomography (SR-XPCT) imaging is an innovative way to quantitatively analyze three-dimensional morphology. XPCT has been employed in this study to evaluate the chordae tendineae from patients with mitral regurgitation and to analyze structural changes in the ruptured chordae tendineae in patients with this condition. Six ruptured mitral chordae tendineae were obtained during surgical repairs for mitral regurgitation and were fixed with formalin. In addition, 12 healthy chordae tendineae were obtained from autopsies. Employing XPCT (effective pixel size, 3.5 µm; density resolution, 1 mg cm−3), the density of the chordae tendineae in each sample was measured. The specimens were subsequently analyzed pathologically. The mean age was 70.2 ± 3.0 in the rupture group and 67.2 ± 14.1 years old in the control group (p = 0.4927). All scans of chorda tendineae with SR-XPCT were performed successfully. The mean densities were 1.029 ± 0.004 in the rupture group and 1.085 ± 0.015 g cm−3 in the control group (p < 0.0001). Density based on SR-XPCT in the ruptured mitral chordae tendineae was significantly lower compared with the healthy chorda tendinea. Histological examination revealed a change in the components of the connective tissues in ruptured chorda tendinea, in accordance with the low density measured by SR-XPCT. SR-XPCT made it possible to measure tissue density in mitral chordae tendineae. Low density in mitral chordae tendineae is associated with a greater fragility in ruptured mitral chordae tendineae.textThe link between the structural properties and the rupturing of chordae tendineae in the mitral valve complex is still unclear. Synchrotron-radiation-based X-ray phase computed tomography (SR-XPCT) imaging is an innovative way to quantitatively analyze three-dimensional morphology. XPCT has been employed in this study to evaluate the chordae tendineae from patients with mitral regurgitation and to analyze structural changes in the ruptured chordae tendineae in patients with this condition. Six ruptured mitral chordae tendineae were obtained during surgical repairs for mitral regurgitation and were fixed with formalin. In addition, 12 healthy chordae tendineae were obtained from autopsies. Employing XPCT (effective pixel size, 3.5 µm; density resolution, 1 mg cm−3), the density of the chordae tendineae in each sample was measured. The specimens were subsequently analyzed pathologically. The mean age was 70.2 ± 3.0 in the rupture group and 67.2 ± 14.1 years old in the control group (p = 0.4927). All scans of chorda tendineae with SR-XPCT were performed successfully. The mean densities were 1.029 ± 0.004 in the rupture group and 1.085 ± 0.015 g cm−3 in the control group (p < 0.0001). Density based on SR-XPCT in the ruptured mitral chordae tendineae was significantly lower compared with the healthy chorda tendinea. Histological examination revealed a change in the components of the connective tissues in ruptured chorda tendinea, in accordance with the low density measured by SR-XPCT. SR-XPCT made it possible to measure tissue density in mitral chordae tendineae. Low density in mitral chordae tendineae is associated with a greater fragility in ruptured mitral chordae tendineae.urn:issn:1600-5775text/htmlTissue density measured by synchrotron-based X-ray phase computed tomography is shown to be associated with the fragility of the ruptured mitral chordae tendineae.2023-08-18SYNCHROTRON-BASED X-RAY PHASE COMPUTED TOMOGRAPHY; MITRAL VALVE; MITRAL CHORDA; MITRAL CHORDA RUPTURE; MITRAL VALVE STRUCTUREStructural properties in ruptured mitral chordae tendineae measured by synchrotron-based X-ray phase computed tomographyInternational Union of CrystallographyKoda, Y.Tsukube, T.Hoshino, M.Yagi, N.Ishibashi-Ueda, H.Okada, K.doi:10.1107/S1600577523005167enhttps://creativecommons.org/licenses/by/4.0/1600-5775research papers995https://creativecommons.org/licenses/by/4.0/52023-08-181600-5775med@iucr.orgJournal of Synchrotron Radiation301002September 2023ID22 – the high-resolution powder-diffraction beamline at ESRF
http://scripts.iucr.org/cgi-bin/paper?vy5010
Following Phase 2 of the upgrade of the ESRF in which the storage ring was replaced by a new low-emittance ring along with many other facility upgrades, the status of ID22, the high-resolution powder-diffraction beamline, is described. The beamline has an in-vacuum undulator as source providing X-rays in the range 6–75 keV. ID22's principle characteristics include very high angular resolution as a result of the highly collimated and monochromatic beam, coupled with a 13-channel Si 111 multi-analyser stage between the sample and a Dectris Eiger2 X 2M-W CdTe pixel detector. The detector's axial resolution allows recorded 2θ values to be automatically corrected for the effects of axial divergence, resulting in narrower and more-symmetric peaks compared with the previous fixed-axial-slit arrangement. The axial acceptance can also be increased with increasing diffraction angle, thus simultaneously improving the statistical quality of high-angle data. A complementary Perkin Elmer XRD1611 medical-imaging detector is available for faster, lower-resolution data, often used at photon energies of 60–70 keV for pair-distribution function analysis, although this is also possible in high-resolution mode by scanning up to 120° 2θ at 35 keV. There are various sample environments, allowing sample temperatures from 4 K to 1600°C, a capillary cell for non-corrosive gas atmospheres in the range 0–100 bar, and a sample-changing robot that can accommodate 75 capillary samples compatible with the temperature range 80 K to 950°C.textFollowing Phase 2 of the upgrade of the ESRF in which the storage ring was replaced by a new low-emittance ring along with many other facility upgrades, the status of ID22, the high-resolution powder-diffraction beamline, is described. The beamline has an in-vacuum undulator as source providing X-rays in the range 6–75 keV. ID22's principle characteristics include very high angular resolution as a result of the highly collimated and monochromatic beam, coupled with a 13-channel Si 111 multi-analyser stage between the sample and a Dectris Eiger2 X 2M-W CdTe pixel detector. The detector's axial resolution allows recorded 2θ values to be automatically corrected for the effects of axial divergence, resulting in narrower and more-symmetric peaks compared with the previous fixed-axial-slit arrangement. The axial acceptance can also be increased with increasing diffraction angle, thus simultaneously improving the statistical quality of high-angle data. A complementary Perkin Elmer XRD1611 medical-imaging detector is available for faster, lower-resolution data, often used at photon energies of 60–70 keV for pair-distribution function analysis, although this is also possible in high-resolution mode by scanning up to 120° 2θ at 35 keV. There are various sample environments, allowing sample temperatures from 4 K to 1600°C, a capillary cell for non-corrosive gas atmospheres in the range 0–100 bar, and a sample-changing robot that can accommodate 75 capillary samples compatible with the temperature range 80 K to 950°C.urn:issn:1600-5775text/htmlThe status of the high-resolution powder-diffraction beamline ID22 at ESRF is described.2023-07-18POWDER X-RAY DIFFRACTION; HIGH RESOLUTION; ESRF; PDF ANALYSISID22 – the high-resolution powder-diffraction beamline at ESRFInternational Union of CrystallographyFitch, A.Dejoie, C.Covacci, E.Confalonieri, G.Grendal, O.Claustre, L.Guillou, P.Kieffer, J.Nolf, W. dePetitdemange, S.Ruat, M.Watier, Y.doi:10.1107/S1600577523004915enhttps://creativecommons.org/licenses/by/4.0/1600-5775beamlines5https://creativecommons.org/licenses/by/4.0/1600-57752023-07-18med@iucr.orgSeptember 2023Journal of Synchrotron Radiation30High-resolution and high-sensitivity X-ray ptychographic coherent diffraction imaging using the CITIUS detector
http://scripts.iucr.org/cgi-bin/paper?yn5101
Ptychographic coherent diffraction imaging (PCDI) is a synchrotron X-ray microscopy technique that provides high spatial resolution and a wide field of view. To improve the performance of PCDI, the performance of the synchrotron radiation source and imaging detector should be improved. In this study, ptychographic diffraction pattern measurements using the CITIUS high-speed X-ray image detector and the corresponding image reconstruction are reported. X-rays with an energy of 6.5 keV were focused by total reflection focusing mirrors, and a flux of ∼2.6 × 1010 photons s−1 was obtained at the sample plane. Diffraction intensity data were collected at up to ∼250 Mcounts s−1 pixel−1 without saturation of the detector. Measurements of tantalum test charts and silica particles and the reconstruction of phase images were performed. A resolution of ∼10 nm and a phase sensitivity of ∼0.01 rad were obtained. The CITIUS detector can be applied to the PCDI observation of various samples using low-emittance synchrotron radiation sources and to the stability evaluation of light sources.textPtychographic coherent diffraction imaging (PCDI) is a synchrotron X-ray microscopy technique that provides high spatial resolution and a wide field of view. To improve the performance of PCDI, the performance of the synchrotron radiation source and imaging detector should be improved. In this study, ptychographic diffraction pattern measurements using the CITIUS high-speed X-ray image detector and the corresponding image reconstruction are reported. X-rays with an energy of 6.5 keV were focused by total reflection focusing mirrors, and a flux of ∼2.6 × 1010 photons s−1 was obtained at the sample plane. Diffraction intensity data were collected at up to ∼250 Mcounts s−1 pixel−1 without saturation of the detector. Measurements of tantalum test charts and silica particles and the reconstruction of phase images were performed. A resolution of ∼10 nm and a phase sensitivity of ∼0.01 rad were obtained. The CITIUS detector can be applied to the PCDI observation of various samples using low-emittance synchrotron radiation sources and to the stability evaluation of light sources.urn:issn:1600-5775text/htmlHigh-resolution and high-sensitivity X-ray ptychographic coherent diffraction imaging is demonstrated using a CITIUS high-speed X-ray image detector.2023-08-01PYCHOGRAPHIC COHERENT DIFFRACTION IMAGING; CITIUSHigh-resolution and high-sensitivity X-ray ptychographic coherent diffraction imaging using the CITIUS detectorInternational Union of CrystallographyTakahashi, Y.Abe, M.Uematsu, H.Takazawa, S.Sasaki, Y.Ishiguro, N.Ozaki, K.Honjo, Y.Nishino, H.Kobayashi, K.Hiraki, T.N.Joti, Y.Hatsui, T.doi:10.1107/S1600577523004897enhttps://creativecommons.org/licenses/by/4.0/1600-5775989research papers5https://creativecommons.org/licenses/by/4.0/1600-57752023-08-01med@iucr.orgSeptember 202399430Journal of Synchrotron RadiationEIGER2 hybrid-photon-counting X-ray detectors for advanced synchrotron diffraction experiments
http://scripts.iucr.org/cgi-bin/paper?gy5047
The ability to utilize a hybrid-photon-counting detector to its full potential can significantly influence data quality, data collection speed, as well as development of elaborate data acquisition schemes. This paper facilitates the optimal use of EIGER2 detectors by providing theory and practical advice on (i) the relation between detector design, technical specifications and operating modes, (ii) the use of corrections and calibrations, and (iii) new acquisition features: a double-gating mode, 8-bit readout mode for increasing temporal resolution, and lines region-of-interest readout mode for frame rates up to 98 kHz. Examples of the implementation and application of EIGER2 at several synchrotron sources (ESRF, PETRA III/DESY, ELETTRA, AS/ANSTO) are presented: high accuracy of high-throughput data in serial crystallography using hard X-rays; suppressing higher harmonics of undulator radiation, improving peak shapes, increasing data collection speed in powder X-ray diffraction; faster ptychography scans; and cleaner and faster pump-and-probe experiments.textThe ability to utilize a hybrid-photon-counting detector to its full potential can significantly influence data quality, data collection speed, as well as development of elaborate data acquisition schemes. This paper facilitates the optimal use of EIGER2 detectors by providing theory and practical advice on (i) the relation between detector design, technical specifications and operating modes, (ii) the use of corrections and calibrations, and (iii) new acquisition features: a double-gating mode, 8-bit readout mode for increasing temporal resolution, and lines region-of-interest readout mode for frame rates up to 98 kHz. Examples of the implementation and application of EIGER2 at several synchrotron sources (ESRF, PETRA III/DESY, ELETTRA, AS/ANSTO) are presented: high accuracy of high-throughput data in serial crystallography using hard X-rays; suppressing higher harmonics of undulator radiation, improving peak shapes, increasing data collection speed in powder X-ray diffraction; faster ptychography scans; and cleaner and faster pump-and-probe experiments.urn:issn:1600-5775text/htmlA presentation of how EIGER2 detectors work and how to best use their newly released features for fast image acquisitions and advanced acquisition schemes.2023-06-21HYBRID PHOTON COUNTING; PIXEL DETECTOR; SILICON; CADMIUM TELLURIDE; COUNT RATE; QUANTUM EFFICIENCY; EIGER2EIGER2 hybrid-photon-counting X-ray detectors for advanced synchrotron diffraction experimentsInternational Union of CrystallographyDonath, T.Šišak Jung, D.Burian, M.Radicci, V.Zambon, P.Fitch, A.N.Dejoie, C.Zhang, B.Ruat, M.Hanfland, M.Kewish, C.M.Riessen, G.A. vanNaumenko, D.Amenitsch, H.Bourenkov, G.Bricogne, G.Chari, A.Schulze-Briese, C.doi:10.1107/S160057752300454Xenhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/723research papersmed@iucr.org1600-57752023-06-21July 202373830Journal of Synchrotron RadiationTowards joint in situ determination of pressure and temperature in the large volume press exclusively from X-ray diffraction
http://scripts.iucr.org/cgi-bin/paper?vl5008
Since high-pressure devices have been used at synchrotron facilities, accurate determination of pressure and temperature in the sample has been a crucial objective, particularly for experiments that simulate the Earth's interior. However, in some cases using a thermocouple may have a high likelihood of failure or is incompatible with a high-pressure assembly. To address these challenges and similar issues, we aim to expand a previously proposed solution: to jointly estimate pressure and temperature (PT) through in situ X-ray diffraction, to cover a wider range of internal PT calibrants tested over larger PT ranges. A modifiable Python-based software is offered to quickly obtain results. To achieve these aims, in situ large volume press experiments are performed on pellets of intimately mixed powders of a halide (NaCl, KCl, KBr, CsCl) or MgO and a metal (Pt, Re, Mo, W, Ni) in the pressure range 3–11 GPa and temperature range 300–1800 K. Although the pressure range was chosen for practical reasons, it also covers an equally important depth range in the Earth (down to 350 km) for geoscience studies. A thermocouple was used to validate the PT conditions in the cell assemblies. The key results show that choosing the appropriate calibrant materials and using a joint PT estimation can yield surprisingly small uncertainties (i.e. <±0.1 GPa and <±50 K). This development is expected to benefit current and future research at extreme conditions, as other materials with high compressibility or high thermal pressure, stable over large PT ranges, may be discovered and used as PT calibrants.textSince high-pressure devices have been used at synchrotron facilities, accurate determination of pressure and temperature in the sample has been a crucial objective, particularly for experiments that simulate the Earth's interior. However, in some cases using a thermocouple may have a high likelihood of failure or is incompatible with a high-pressure assembly. To address these challenges and similar issues, we aim to expand a previously proposed solution: to jointly estimate pressure and temperature (PT) through in situ X-ray diffraction, to cover a wider range of internal PT calibrants tested over larger PT ranges. A modifiable Python-based software is offered to quickly obtain results. To achieve these aims, in situ large volume press experiments are performed on pellets of intimately mixed powders of a halide (NaCl, KCl, KBr, CsCl) or MgO and a metal (Pt, Re, Mo, W, Ni) in the pressure range 3–11 GPa and temperature range 300–1800 K. Although the pressure range was chosen for practical reasons, it also covers an equally important depth range in the Earth (down to 350 km) for geoscience studies. A thermocouple was used to validate the PT conditions in the cell assemblies. The key results show that choosing the appropriate calibrant materials and using a joint PT estimation can yield surprisingly small uncertainties (i.e. <±0.1 GPa and <±50 K). This development is expected to benefit current and future research at extreme conditions, as other materials with high compressibility or high thermal pressure, stable over large PT ranges, may be discovered and used as PT calibrants.urn:issn:1600-5775text/htmlResearch in high-pressure devices, such as the diamond anvil cell and the large volume press, requires knowledge of the pressure and temperature in the sample. Here, a large volume press and an internal resistive heater were used to generate high load and heat to various combinations of intimately mixed powders of materials. X-ray diffraction and custom software were used to jointly estimate the pressures and temperatures in the samples and establish calibrants for in situ experiments at extreme conditions.2023-06-21EQUATIONS OF STATE; X-RAY DIFFRACTION; LARGE VOLUME PRESS; HIGH PRESSURE; RESISTIVE HEATINGTowards joint in situ determination of pressure and temperature in the large volume press exclusively from X-ray diffractionInternational Union of CrystallographyFarla, R.doi:10.1107/S1600577523004538enhttps://creativecommons.org/licenses/by/4.0/814Journal of Synchrotron Radiation30July 2023med@iucr.org2023-06-211600-57754https://creativecommons.org/licenses/by/4.0/short communications8071600-5775Soft X-ray beamline BL1N2 at Aichi Synchrotron Radiation Center and its industrial use
http://scripts.iucr.org/cgi-bin/paper?ay5616
BL1N2 is a soft X-ray XAFS (X-ray absorption fine structure) beamline that is well suited for industrial use. User service started in 2015. The beamline is a grazing optical system with a pre-mirror, an inlet slit, two mirrors for three gratings, an outlet slit and a post-mirror. Light of 150 eV to 2000 eV is available, and K-edge measurements of elements from B to Si are covered. The O K-edge is most often measured; transition metals such as Ni and Cu at their L-edges and lanthanoids at their M-edges are also often measured. Here, basic information about BL1N2, the effect of ageing by synchrotron radiation to remove mirror contamination, and a compatible sample handling system and transfer vessels to allow a one-stop service at three soft X-ray beamlines at AichiSR are described.textBL1N2 is a soft X-ray XAFS (X-ray absorption fine structure) beamline that is well suited for industrial use. User service started in 2015. The beamline is a grazing optical system with a pre-mirror, an inlet slit, two mirrors for three gratings, an outlet slit and a post-mirror. Light of 150 eV to 2000 eV is available, and K-edge measurements of elements from B to Si are covered. The O K-edge is most often measured; transition metals such as Ni and Cu at their L-edges and lanthanoids at their M-edges are also often measured. Here, basic information about BL1N2, the effect of ageing by synchrotron radiation to remove mirror contamination, and a compatible sample handling system and transfer vessels to allow a one-stop service at three soft X-ray beamlines at AichiSR are described.urn:issn:1600-5775text/htmlBasic information about beamline BL1N2, the effect of ageing by synchrotron radiation to suppress mirror contamination, and efforts to support industrial use are reported.2023-06-20SOFT X-RAY XAFS; MIRROR CONTAMINATION; INDUSTRIAL USESoft X-ray beamline BL1N2 at Aichi Synchrotron Radiation Center and its industrial useInternational Union of CrystallographySugiyama, H.Murase, H.Nomoto, T.Takeda, Y.doi:10.1107/S1600577523004423enhttps://creativecommons.org/licenses/by/4.0/85430Journal of Synchrotron RadiationJuly 2023med@iucr.org2023-06-201600-57754https://creativecommons.org/licenses/by/4.0/beamlines8471600-5775In situ X-ray area detector flat-field correction at an operating photon energy without flat illumination. Corrigendum
http://scripts.iucr.org/cgi-bin/paper?gy9043
The name of an author in the article by Weng et al. (2023) [J. Synchrotron Rad. 30, 546–554] is corrected.textThe name of an author in the article by Weng et al. (2023) [J. Synchrotron Rad. 30, 546–554] is corrected.urn:issn:1600-5775text/htmlCorrigendum to the article by Weng et al. (2023) [J. Synchrotron Rad. 30, 546–554].2023-05-26FLAT-FIELD CORRECTION; FLAT-FIELD CALIBRATION; DECTECTOR DRIFTIn situ X-ray area detector flat-field correction at an operating photon energy without flat illumination. CorrigendumInternational Union of CrystallographyWeng, J.Xu, W.Wiaderek, K.M.Borkiewicz, O.J.Chen, J.Von Dreele, R.B.Gallington, L.C.Ruett, U.doi:10.1107/S1600577523004320enhttps://creativecommons.org/licenses/by/4.0/855Journal of Synchrotron Radiation30July 20232023-05-261600-5775med@iucr.orgaddenda and errata8554https://creativecommons.org/licenses/by/4.0/1600-5775Translocation and fate of nanospheres in pheochromocytoma cells following exposure to synchrotron-sourced terahertz radiation
http://scripts.iucr.org/cgi-bin/paper?ok5095
The routes by which foreign objects enter cells is well studied; however, their fate following uptake has not been explored extensively. Following exposure to synchrotron-sourced (SS) terahertz (THz) radiation, reversible membrane permeability has been demonstrated in eukaryotic cells by the uptake of nanospheres; nonetheless, cellular localization of the nanospheres remained unclear. This study utilized silica core-shell gold nanospheres (AuSi NS) of diameter 50 ± 5 nm to investigate the fate of nanospheres inside pheochromocytoma (PC 12) cells following SS THz exposure. Fluorescence microscopy was used to confirm nanosphere internalization following 10 min of SS THz exposure in the range 0.5–20 THz. Transmission electron microscopy followed by scanning transmission electron microscopy energy-dispersive spectroscopic (STEM-EDS) analysis was used to confirm the presence of AuSi NS in the cytoplasm or membrane, as single NS or in clusters (22% and 52%, respectively), with the remainder (26%) sequestered in vacuoles. Cellular uptake of NS in response to SS THz radiation could have suitable applications in a vast number of biomedical applications, regenerative medicine, vaccines, cancer therapy, gene and drug delivery.textThe routes by which foreign objects enter cells is well studied; however, their fate following uptake has not been explored extensively. Following exposure to synchrotron-sourced (SS) terahertz (THz) radiation, reversible membrane permeability has been demonstrated in eukaryotic cells by the uptake of nanospheres; nonetheless, cellular localization of the nanospheres remained unclear. This study utilized silica core-shell gold nanospheres (AuSi NS) of diameter 50 ± 5 nm to investigate the fate of nanospheres inside pheochromocytoma (PC 12) cells following SS THz exposure. Fluorescence microscopy was used to confirm nanosphere internalization following 10 min of SS THz exposure in the range 0.5–20 THz. Transmission electron microscopy followed by scanning transmission electron microscopy energy-dispersive spectroscopic (STEM-EDS) analysis was used to confirm the presence of AuSi NS in the cytoplasm or membrane, as single NS or in clusters (22% and 52%, respectively), with the remainder (26%) sequestered in vacuoles. Cellular uptake of NS in response to SS THz radiation could have suitable applications in a vast number of biomedical applications, regenerative medicine, vaccines, cancer therapy, gene and drug delivery.urn:issn:1600-5775text/htmlSynchrotron-sourced radiation-driven internalization and localization of nanospheres inside mammalian cells.2023-06-20FATE OF NANOSPHERES; ELECTROMAGNETIC FIELDS (EMFS); SYNCHROTRON-SOURCED THZ RADIATION; PC 12 NEURONAL CELLS; MEMBRANE PERMEABILITYTranslocation and fate of nanospheres in pheochromocytoma cells following exposure to synchrotron-sourced terahertz radiationInternational Union of CrystallographyPerera, P.G.T.Vilagosh, Z.Linklater, D.Nguyen, T.H.P.Appadoo, D.Vongsvivut, J.Tobin, M.Dekiwadia, C.Croft, R.Ivanova, E.P.doi:10.1107/S1600577523004228enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752023-06-20July 2023787Journal of Synchrotron Radiation301600-57754https://creativecommons.org/licenses/by/4.0/780research papersA compact gas attenuator for the SwissFEL ATHOS beamline realized using additive manufacturing
http://scripts.iucr.org/cgi-bin/paper?rv5173
Gas attenuators are important devices providing accurate variation of photon intensity for soft X-ray beamlines. In the SwissFEL ATHOS beamline front-end the space is very limited and an innovative approach has been taken to provide attenuation of three orders of magnitude up to an energy of 1200 eV. Additive manufacturing of a differential pumping system vacuum manifold allowed a triple pumping stage to be realized in a space of less than half a meter. Measurements have shown that the response of the device is as expected from theoretical calculations.textGas attenuators are important devices providing accurate variation of photon intensity for soft X-ray beamlines. In the SwissFEL ATHOS beamline front-end the space is very limited and an innovative approach has been taken to provide attenuation of three orders of magnitude up to an energy of 1200 eV. Additive manufacturing of a differential pumping system vacuum manifold allowed a triple pumping stage to be realized in a space of less than half a meter. Measurements have shown that the response of the device is as expected from theoretical calculations.urn:issn:1600-5775text/htmlA compact gas attenuator for the SwissFEL ATHOS beamline with a custom manifold realized using additive manufacturing is described. First results show that the response is as expected from theoretical calculations.2023-05-30X-RAY FREE-ELECTRON LASERS; GAS ATTENUATOR; ADDITIVE MANUFACTURINGA compact gas attenuator for the SwissFEL ATHOS beamline realized using additive manufacturingInternational Union of CrystallographyPradervand, C.Rosenberg, C.Eckerlin, H.-J.Schnorr, K.Al Haddad, A.Wiegand, P.Hess, C.Gaiffi, N.Patthey, L.doi:10.1107/S1600577523004241enhttps://creativecommons.org/licenses/by/4.0/July 202330Journal of Synchrotron Radiation7221600-57752023-05-30med@iucr.org717research papershttps://creativecommons.org/licenses/by/4.0/41600-5775Towards a wavefront-preservation X-ray crystal monochromator for high-repetition-rate FELs
http://scripts.iucr.org/cgi-bin/paper?ve5169
The wavefront preservation of coherent X-ray free-electron laser beams is pushing the requirement on the quality and performance of X-ray optics to an unprecedented level. The Strehl ratio can be used to quantify this requirement. In this paper, the criteria for thermal deformation of the X-ray optics are formulated, especially for crystal monochromators. To preserve the X-ray wavefront, the standard deviation of the height error should be sub-nm for mirrors and less than 25 pm for crystal monochromators. Cryocooled silicon crystals combined with two techniques can be used to achieve this level of performance for monochromator crystals: (1) using a focusing element to compensate the second-order component of the thermal deformation; (2) introducing a cooling pad between the cooling block and silicon crystal and optimizing the effective cooling temperature. Each of these techniques allows the thermal deformation in standard deviation of the height error to be reduced by an order of magnitude. As an example, for the LCLS-II-HE Dynamic X-ray Scattering instrument, the criteria on thermal deformation of a high-heat-load monochromator crystal can be achieved for a 100 W SASE FEL beam. Wavefront propagation simulations confirm that the reflected beam intensity profile is satisfactory on both the peak power density and focused beam size.textThe wavefront preservation of coherent X-ray free-electron laser beams is pushing the requirement on the quality and performance of X-ray optics to an unprecedented level. The Strehl ratio can be used to quantify this requirement. In this paper, the criteria for thermal deformation of the X-ray optics are formulated, especially for crystal monochromators. To preserve the X-ray wavefront, the standard deviation of the height error should be sub-nm for mirrors and less than 25 pm for crystal monochromators. Cryocooled silicon crystals combined with two techniques can be used to achieve this level of performance for monochromator crystals: (1) using a focusing element to compensate the second-order component of the thermal deformation; (2) introducing a cooling pad between the cooling block and silicon crystal and optimizing the effective cooling temperature. Each of these techniques allows the thermal deformation in standard deviation of the height error to be reduced by an order of magnitude. As an example, for the LCLS-II-HE Dynamic X-ray Scattering instrument, the criteria on thermal deformation of a high-heat-load monochromator crystal can be achieved for a 100 W SASE FEL beam. Wavefront propagation simulations confirm that the reflected beam intensity profile is satisfactory on both the peak power density and focused beam size.urn:issn:1600-5775text/htmlThe thermal deformation requirement for wavefront preservation through an X-ray crystal monochromator is found to restrict the standard deviation of the height error to less than 25 pm under certain conditions. By optimizing the effective cooling temperature of liquid-nitrogen-cooled crystals, combined with compensation of the second-order component of the thermal deformation, an approach to reach this unprecedented requirement is described.2023-06-15X-RAY OPTICS; MONOCHROMATOR CRYSTAL; THERMAL DEFORMATION; WAVEFRONT PRESERVATION; STREHL RATIO; FELTowards a wavefront-preservation X-ray crystal monochromator for high-repetition-rate FELsInternational Union of CrystallographyZhang, L.Seaberg, M.Yavaş, H.doi:10.1107/S1600577523004216enhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/686research papersmed@iucr.org2023-06-151600-5775694Journal of Synchrotron Radiation30July 2023Quantitative alignment parameter estimation for analyzing X-ray photoelectron spectra
http://scripts.iucr.org/cgi-bin/paper?ok5090
The interpretation of X-ray photoelectron spectroscopy (XPS) data relies on measurement models that depend on several parameters, including the photoelectron attenuation length and X-ray photon flux. However, some of these parameters are not known, because they are not or cannot be measured. The unknown geometrical parameters can be lumped together in a multiplicative factor, the alignment parameter. This parameter characterizes the ability of the exciting light to interact with the sample. Unfortunately, the absolute value of the alignment parameter cannot be measured directly, in part because it depends on the measurement model. Instead, a proxy for the experimental alignment is often estimated, which is closely related to the alignment parameter. Here, a method for estimating the absolute value of the alignment parameter based on the raw XPS spectra (i.e. non-processed photoelectron counts), the geometry of the sample and the photoelectron attenuation length is presented. The proposed parameter estimation method enables the quantitative analysis of XPS spectra using a simplified measurement model. All computations can be executed within the open and free Julia language framework PROPHESY. To demonstrate feasibility, the alignment parameter estimation method is first tested on simulated data with known acquisition parameters. The method is then applied to experimental XPS data and a strong correlation between the estimated alignment parameter and the typically used alignment proxy is shown.textThe interpretation of X-ray photoelectron spectroscopy (XPS) data relies on measurement models that depend on several parameters, including the photoelectron attenuation length and X-ray photon flux. However, some of these parameters are not known, because they are not or cannot be measured. The unknown geometrical parameters can be lumped together in a multiplicative factor, the alignment parameter. This parameter characterizes the ability of the exciting light to interact with the sample. Unfortunately, the absolute value of the alignment parameter cannot be measured directly, in part because it depends on the measurement model. Instead, a proxy for the experimental alignment is often estimated, which is closely related to the alignment parameter. Here, a method for estimating the absolute value of the alignment parameter based on the raw XPS spectra (i.e. non-processed photoelectron counts), the geometry of the sample and the photoelectron attenuation length is presented. The proposed parameter estimation method enables the quantitative analysis of XPS spectra using a simplified measurement model. All computations can be executed within the open and free Julia language framework PROPHESY. To demonstrate feasibility, the alignment parameter estimation method is first tested on simulated data with known acquisition parameters. The method is then applied to experimental XPS data and a strong correlation between the estimated alignment parameter and the typically used alignment proxy is shown.urn:issn:1600-5775text/htmlA model of an X-ray photoelectron spectroscopy experiment accounting for photon beam asperities, sample geometry and kinetic energy analyzer is introduced. This model is related via the alignment parameter to a simple model commonly used for data interpretation. An alignment parameter estimation method is introduced and tested with simulated and experimental data.2023-06-16X-RAY PHOTOELECTRON SPECTROSCOPY; EXPERIMENTAL ALIGNMENT PARAMETER; MEASUREMENT MODEL; LIQUID JET; QUANTITATIVE DATA INVERSIONQuantitative alignment parameter estimation for analyzing X-ray photoelectron spectraInternational Union of CrystallographyOzon, M.Tumashevich, K.Prisle, N.L.doi:10.1107/S1600577523004150enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org2023-06-161600-5775779Journal of Synchrotron Radiation30July 20231600-57754https://creativecommons.org/licenses/by/4.0/research papers766High-pressure single-crystal diffraction at the Australian Synchrotron
http://scripts.iucr.org/cgi-bin/paper?vy5009
A new high-pressure single-crystal diffraction setup has been designed and implemented at the Australian Synchrotron for collecting molecular and protein crystal structures. The setup incorporates a modified micro-Merrill–Bassett cell and holder designed specifically to fit onto the horizontal air-bearing goniometer, allowing high-pressure diffraction measurements to be collected with little to no modification of the beamline setup compared with ambient data collections. Compression data for the amino acid, l-threonine, and the protein, hen egg-white lysozyme, were collected, showcasing the capabilities of the setup.textA new high-pressure single-crystal diffraction setup has been designed and implemented at the Australian Synchrotron for collecting molecular and protein crystal structures. The setup incorporates a modified micro-Merrill–Bassett cell and holder designed specifically to fit onto the horizontal air-bearing goniometer, allowing high-pressure diffraction measurements to be collected with little to no modification of the beamline setup compared with ambient data collections. Compression data for the amino acid, l-threonine, and the protein, hen egg-white lysozyme, were collected, showcasing the capabilities of the setup.urn:issn:1600-5775text/htmlA new high-pressure single-crystal diffraction setup has been designed and implemented at the Australian Synchrotron for collecting molecular and protein crystal structures.2023-06-15PRESSURE; SYNCHROTRON; SINGLE CRYSTALHigh-pressure single-crystal diffraction at the Australian SynchrotronInternational Union of CrystallographyBoer, S.A.Price, J.R.Riboldi-Tunnicliffe, A.Williamson, R.Rostan, R.Summers, A.Turner, G.F.Jones, I.Bond, C.S.Vrielink, A.Marshall, A.C.Hitchings, J.Moggach, S.A.doi:10.1107/S160057752300406Xenhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/beamlines841med@iucr.org1600-57752023-06-15July 202384630Journal of Synchrotron RadiationA MHz X-ray diffraction set-up for dynamic compression experiments in the diamond anvil cell
http://scripts.iucr.org/cgi-bin/paper?fv5162
An experimental platform for dynamic diamond anvil cell (dDAC) research has been developed at the High Energy Density (HED) Instrument at the European X-ray Free Electron Laser (European XFEL). Advantage was taken of the high repetition rate of the European XFEL (up to 4.5 MHz) to collect pulse-resolved MHz X-ray diffraction data from samples as they are dynamically compressed at intermediate strain rates (≤103 s−1), where up to 352 diffraction images can be collected from a single pulse train. The set-up employs piezo-driven dDACs capable of compressing samples in ≥340 µs, compatible with the maximum length of the pulse train (550 µs). Results from rapid compression experiments on a wide range of sample systems with different X-ray scattering powers are presented. A maximum compression rate of 87 TPa s−1 was observed during the fast compression of Au, while a strain rate of ∼1100 s−1 was achieved during the rapid compression of N2 at 23 TPa s−1.textAn experimental platform for dynamic diamond anvil cell (dDAC) research has been developed at the High Energy Density (HED) Instrument at the European X-ray Free Electron Laser (European XFEL). Advantage was taken of the high repetition rate of the European XFEL (up to 4.5 MHz) to collect pulse-resolved MHz X-ray diffraction data from samples as they are dynamically compressed at intermediate strain rates (≤103 s−1), where up to 352 diffraction images can be collected from a single pulse train. The set-up employs piezo-driven dDACs capable of compressing samples in ≥340 µs, compatible with the maximum length of the pulse train (550 µs). Results from rapid compression experiments on a wide range of sample systems with different X-ray scattering powers are presented. A maximum compression rate of 87 TPa s−1 was observed during the fast compression of Au, while a strain rate of ∼1100 s−1 was achieved during the rapid compression of N2 at 23 TPa s−1.urn:issn:1600-5775text/htmlA MHz X-ray diffraction set-up for the investigation of material behaviour under dynamic compression in a diamond anvil cell at intermediate strain rates has been developed at the High Energy Density (HED) instrument at the European XFEL.2023-06-15EXTREME CONDITIONS SCIENCE; X-RAY FREE-ELECTRON LASERS; DIAMOND ANVIL CELLS; DYNAMIC COMPRESSIONA MHz X-ray diffraction set-up for dynamic compression experiments in the diamond anvil cellInternational Union of CrystallographyHusband, R.J.Strohm, C.Appel, K.Ball, O.B.Briggs, R.Buchen, J.Cerantola, V.Chariton, S.Coleman, A.L.Cynn, H.Dattelbaum, D.Dwivedi, A.Eggert, J.H.Ehm, L.Evans, W.J.Glazyrin, K.Goncharov, A.F.Graafsma, H.Howard, A.Huston, L.Hutchinson, T.M.Hwang, H.Jacob, S.Kaa, J.Kim, J.Kim, M.Koemets, E.Konôpková, Z.Langenhorst, F.Laurus, T.Li, X.Mainberger, J.Marquardt, H.McBride, E.E.McGuire, C.McHardy, J.D.McMahon, M.I.McWilliams, R.S.Méndez, A.S.J.Mondal, A.Morard, G.O'Bannon, E.F.Otzen, C.Pépin, C.M.Prakapenka, V.B.Prescher, C.Preston, T.R.Redmer, R.Roeper, M.Sanchez-Valle, C.Smith, D.Smith, R.F.Sneed, D.Speziale, S.Spitzbart, T.Stern, S.Sturtevant, B.T.Sztuk-Dambietz, J.Talkovski, P.Velisavljevic, N.Vennari, C.Wu, Z.Yoo, C.-S.Zastrau, U.Jenei, Z.Liermann, H.-P.doi:10.1107/S1600577523003910enhttps://creativecommons.org/licenses/by/4.0/4https://creativecommons.org/licenses/by/4.0/research papers6711600-5775July 2023685Journal of Synchrotron Radiation30med@iucr.org1600-57752023-06-15Micropipette aspiration as a tool for single-particle X-ray imaging and diffraction
http://scripts.iucr.org/cgi-bin/paper?ju5051
A sample environment and manipulation tool is presented for single-particle X-ray experiments in an aqueous environment. The system is based on a single water droplet, positioned on a substrate that is structured by a hydrophobic and hydrophilic pattern to stabilize the droplet position. The substrate can support several droplets at a time. Evaporation is prevented by covering the droplet by a thin film of mineral oil. In this windowless fluid which minimizes background signal, single particles can be probed and manipulated by micropipettes, which can easily be inserted and steered in the droplet. Holographic X-ray imaging is shown to be well suited to observe and monitor the pipettes, as well as the droplet surface and the particles. Aspiration and force generation are also enabled based on an application of controlled pressure differences. Experimental challenges are addressed and first results are presented, obtained at two different undulator endstations with nano-focused beams. Finally, the sample environment is discussed in view of future coherent imaging and diffraction experiments with synchrotron radiation and single X-ray free-electron laser pulses.textA sample environment and manipulation tool is presented for single-particle X-ray experiments in an aqueous environment. The system is based on a single water droplet, positioned on a substrate that is structured by a hydrophobic and hydrophilic pattern to stabilize the droplet position. The substrate can support several droplets at a time. Evaporation is prevented by covering the droplet by a thin film of mineral oil. In this windowless fluid which minimizes background signal, single particles can be probed and manipulated by micropipettes, which can easily be inserted and steered in the droplet. Holographic X-ray imaging is shown to be well suited to observe and monitor the pipettes, as well as the droplet surface and the particles. Aspiration and force generation are also enabled based on an application of controlled pressure differences. Experimental challenges are addressed and first results are presented, obtained at two different undulator endstations with nano-focused beams. Finally, the sample environment is discussed in view of future coherent imaging and diffraction experiments with synchrotron radiation and single X-ray free-electron laser pulses.urn:issn:1600-5775text/htmlMicropipette aspiration has been combined with a windowless hydrated sample environment for single-particle X-ray analysis. A water droplet serves as a `chamber', covered by a mineral oil to prevent evaporation. In the droplet, particles can be aspirated and manipulated by one or two micropipettes. The system was evaluated on two undulator beamlines, using grains, giant lipid vesicles, colloids and macrophages as test objects. Holographic near-field images were recorded.2023-05-26MICROPIPETTE ASPIRATION; HOLOGRAPHIC X-RAY IMAGING; SINGLE-PARTICLE DIFFRACTION; SAMPLE DELIVERY OF BIOPHYSICAL SAMPLESMicropipette aspiration as a tool for single-particle X-ray imaging and diffractionInternational Union of CrystallographyBruns, H.Hoeppe, H.Bellec, E.Leake, S.Osterhoff, M.Salditt, T.doi:10.1107/S1600577523003685enhttps://creativecommons.org/licenses/by/4.0/research papers788https://creativecommons.org/licenses/by/4.0/41600-5775July 2023Journal of Synchrotron Radiation307951600-57752023-05-26med@iucr.orgX-ray mirrors with sub-nanometre figure errors obtained by differential deposition of thin WSi2 films
http://scripts.iucr.org/cgi-bin/paper?ye5032
Differential deposition by DC magnetron sputtering was applied to correct for figure errors of X-ray mirrors to be deployed on low-emittance synchrotron beamlines. During the deposition process, the mirrors were moved in front of a beam-defining aperture and the required velocity profile was calculated using a deconvolution algorithm. The surface figure was characterized using conventional off-line visible-light metrology instrumentation (long trace profiler and Fizeau interferometer) before and after the deposition. WSi2 was revealed to be a promising candidate material since it conserves the initial substrate surface roughness and limits the film stress to acceptable levels. On a 300 mm-long flat Si mirror the average height errors were reduced by a factor of 20 down to 0.2 nm root mean square. This result shows the suitability of WSi2 for differential deposition. Potential promising applications include the upgrade of affordable, average-quality substrates to the standards of modern synchrotron beamlines.textDifferential deposition by DC magnetron sputtering was applied to correct for figure errors of X-ray mirrors to be deployed on low-emittance synchrotron beamlines. During the deposition process, the mirrors were moved in front of a beam-defining aperture and the required velocity profile was calculated using a deconvolution algorithm. The surface figure was characterized using conventional off-line visible-light metrology instrumentation (long trace profiler and Fizeau interferometer) before and after the deposition. WSi2 was revealed to be a promising candidate material since it conserves the initial substrate surface roughness and limits the film stress to acceptable levels. On a 300 mm-long flat Si mirror the average height errors were reduced by a factor of 20 down to 0.2 nm root mean square. This result shows the suitability of WSi2 for differential deposition. Potential promising applications include the upgrade of affordable, average-quality substrates to the standards of modern synchrotron beamlines.urn:issn:1600-5775text/htmlThe surface figure of an X-ray mirror has been corrected by differential deposition of WSi2 films.2023-05-30X-RAY OPTICS; FIGURE CORRECTION; DIFFERENTIAL DEPOSITION; SURFACE ROUGHNESS; FILMSTRESS; OFF-LINE METROLOGY; FIZEAU STITCHING; LONG TRACE PROFILER; MAGNETRON SPUTTERINGX-ray mirrors with sub-nanometre figure errors obtained by differential deposition of thin WSi2 filmsInternational Union of CrystallographyBras, P.Morawe, C.Labouré, S.Perrin, F.Vivo, A.Barrett, R.doi:10.1107/S1600577523003697enhttps://creativecommons.org/licenses/by/4.0/med@iucr.org1600-57752023-05-30July 202371630Journal of Synchrotron Radiation1600-57754https://creativecommons.org/licenses/by/4.0/708research papersMapping nanocrystal orientations via scanning Laue diffraction microscopy for multi-peak Bragg coherent diffraction imaging
http://scripts.iucr.org/cgi-bin/paper?ay5613
The recent commissioning of a movable monochromator at the 34-ID-C endstation of the Advanced Photon Source has vastly simplified the collection of Bragg coherent diffraction imaging (BCDI) data from multiple Bragg peaks of sub-micrometre scale samples. Laue patterns arising from the scattering of a polychromatic beam by arbitrarily oriented nanocrystals permit their crystal orientations to be computed, which are then used for locating and collecting several non-co-linear Bragg reflections. The volumetric six-component strain tensor is then constructed by combining the projected displacement fields that are imaged using each of the measured reflections via iterative phase retrieval algorithms. Complications arise when the sample is heterogeneous in composition and/or when multiple grains of a given lattice structure are simultaneously illuminated by the polychromatic beam. Here, a workflow is established for orienting and mapping nanocrystals on a substrate of a different material using scanning Laue diffraction microscopy. The capabilities of the developed algorithms and procedures with both synthetic and experimental data are demonstrated. The robustness is verified by comparing experimental texture maps obtained with Laue diffraction microscopy at the beamline with maps obtained from electron back-scattering diffraction measurements on the same patch of gold nanocrystals. Such tools provide reliable indexing for both isolated and densely distributed nanocrystals, which are challenging to image in three dimensions with other techniques.textThe recent commissioning of a movable monochromator at the 34-ID-C endstation of the Advanced Photon Source has vastly simplified the collection of Bragg coherent diffraction imaging (BCDI) data from multiple Bragg peaks of sub-micrometre scale samples. Laue patterns arising from the scattering of a polychromatic beam by arbitrarily oriented nanocrystals permit their crystal orientations to be computed, which are then used for locating and collecting several non-co-linear Bragg reflections. The volumetric six-component strain tensor is then constructed by combining the projected displacement fields that are imaged using each of the measured reflections via iterative phase retrieval algorithms. Complications arise when the sample is heterogeneous in composition and/or when multiple grains of a given lattice structure are simultaneously illuminated by the polychromatic beam. Here, a workflow is established for orienting and mapping nanocrystals on a substrate of a different material using scanning Laue diffraction microscopy. The capabilities of the developed algorithms and procedures with both synthetic and experimental data are demonstrated. The robustness is verified by comparing experimental texture maps obtained with Laue diffraction microscopy at the beamline with maps obtained from electron back-scattering diffraction measurements on the same patch of gold nanocrystals. Such tools provide reliable indexing for both isolated and densely distributed nanocrystals, which are challenging to image in three dimensions with other techniques.urn:issn:1600-5775text/htmlA workflow for orienting and mapping nanocrystals on a substrate of a different material lattice using scanning Laue diffraction microscopy has been established.2023-05-30LAUE DIFFRACTION; BCDI; SYNCHROTRON; BRAGG DIFFRACTIONMapping nanocrystal orientations via scanning Laue diffraction microscopy for multi-peak Bragg coherent diffraction imagingInternational Union of CrystallographyZhang, Y.Porter, J.N.Wilkin, M.J.Harder, R.Cha, W.Suter, R.M.Liu, H.Schnebly, L.Sandberg, R.L.Miller, J.A.Tischler, J.Pateras, A.Rollett, A.D.doi:10.1107/S160057752300365Xenhttps://creativecommons.org/licenses/by/4.0/research papers796https://creativecommons.org/licenses/by/4.0/41600-5775July 2023Journal of Synchrotron Radiation308061600-57752023-05-30med@iucr.orgPhase segregation and miscibility of TiOx nanocomposites in Gd-doped ceria solid electrolyte material
http://scripts.iucr.org/cgi-bin/paper?ok5092
Electro-chemo-mechanical (ECM) coupling refers to mechanical deformation due to electrochemically driven compositional change in a solid. An ECM actuator producing micrometre-size displacements and long-term stability at room temperature was recently reported, comprising a 20 mol% Gd-doped ceria (20GDC), a solid electrolyte membrane, placed between two working bodies made of TiOx/20GDC (Ti-GDC) nanocomposites with Ti concentration of 38 mol%. The volumetric changes originating from oxidation or reduction in the local TiOx units are hypothesized to be the origin of mechanical deformation in the ECM actuator. Studying the Ti concentration-dependent structural changes in the Ti-GDC nanocomposites is therefore required for (i) understanding the mechanism of dimensional changes in the ECM actuator and (ii) maximizing the ECM response. Here, the systematic investigation of the local structure of the Ti and Ce ions in Ti-GDC over a broad range of Ti concentrations using synchrotron X-ray absorption spectroscopy and X-ray diffraction is reported. The main finding is that, depending on the Ti concentration, Ti atoms either form a cerium titanate or segregate into a TiO2 anatase-like phase. The transition region between these two regimes with Ti(IV) concentration between 19% and 57% contained strongly disordered TiOx units dispersed in 20GDC containing Ce(III) and Ce(IV) and hence rich with oxygen vacancies. As a result, this transition region is proposed to be the most advantageous for developing ECM-active materials.textElectro-chemo-mechanical (ECM) coupling refers to mechanical deformation due to electrochemically driven compositional change in a solid. An ECM actuator producing micrometre-size displacements and long-term stability at room temperature was recently reported, comprising a 20 mol% Gd-doped ceria (20GDC), a solid electrolyte membrane, placed between two working bodies made of TiOx/20GDC (Ti-GDC) nanocomposites with Ti concentration of 38 mol%. The volumetric changes originating from oxidation or reduction in the local TiOx units are hypothesized to be the origin of mechanical deformation in the ECM actuator. Studying the Ti concentration-dependent structural changes in the Ti-GDC nanocomposites is therefore required for (i) understanding the mechanism of dimensional changes in the ECM actuator and (ii) maximizing the ECM response. Here, the systematic investigation of the local structure of the Ti and Ce ions in Ti-GDC over a broad range of Ti concentrations using synchrotron X-ray absorption spectroscopy and X-ray diffraction is reported. The main finding is that, depending on the Ti concentration, Ti atoms either form a cerium titanate or segregate into a TiO2 anatase-like phase. The transition region between these two regimes with Ti(IV) concentration between 19% and 57% contained strongly disordered TiOx units dispersed in 20GDC containing Ce(III) and Ce(IV) and hence rich with oxygen vacancies. As a result, this transition region is proposed to be the most advantageous for developing ECM-active materials.urn:issn:1600-5775text/htmlThe local structure of titania–ceria composites in a Gd-doped ceria solid electrolyte material is obtained by a combination of X-ray absorption fine structure and X-ray diffraction over the entire range of Ti composition. A compositional region (between 19 and 57%) with strongly distorted TiO6 units and coexistence of Ce(III) and Ce(IV) was discovered, i.e. optimized for oxygen transport conduction and in agreement with the enhanced electro-chemo-mechanical effect previously observed in this composition range.2023-05-26X-RAY ABSORPTION SPECTROSCOPY; ELECTRO-CHEMO-MECHANICAL EFFECT; LOCAL STRUCTURAL DISORDERPhase segregation and miscibility of TiOx nanocomposites in Gd-doped ceria solid electrolyte materialInternational Union of CrystallographyLi, J.Routh, P.K.Li, Y.Plonka, A.Makagon, E.Lubomirsky, I.Frenkel, A.doi:10.1107/S1600577523003636enhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/758research papersmed@iucr.org2023-05-261600-5775765Journal of Synchrotron Radiation30July 2023Analysis of the dislocation activity of Mg–Zn–Y alloy using synchrotron radiation under tensile loading
http://scripts.iucr.org/cgi-bin/paper?vl5009
An understanding of deformation behavior and texture development is crucial for the formability improvement of Mg alloys. X-ray line profile analysis using the convolutional multiple whole profile (CMWP) fitting method allows the experimental determination of dislocation densities separately for different Burgers vectors up to a high deformation degree. A wider use of this technique still requires exploration and testing of various materials. In this regard, the reliability of the CMWP fitting method for Mg–Zn–Y alloys, in terms of the dislocation activity during tensile deformation, was verified in the present study by the combined analysis of electron backscatter diffraction (EBSD) investigation and visco-plastic self-consistent (VPSC) simulation. The predominant activity of non-basal 〈a〉 dislocation slip was revealed by CMWP analysis, and Schmid factor analysis from the EBSD results supported the higher potential of non-basal dislocation slip in comparison with basal 〈a〉 dislocation slip. Moreover, the relative slip activities obtained by the VPSC simulation also show a similar trend to those obtained from the CMWP evaluation.textAn understanding of deformation behavior and texture development is crucial for the formability improvement of Mg alloys. X-ray line profile analysis using the convolutional multiple whole profile (CMWP) fitting method allows the experimental determination of dislocation densities separately for different Burgers vectors up to a high deformation degree. A wider use of this technique still requires exploration and testing of various materials. In this regard, the reliability of the CMWP fitting method for Mg–Zn–Y alloys, in terms of the dislocation activity during tensile deformation, was verified in the present study by the combined analysis of electron backscatter diffraction (EBSD) investigation and visco-plastic self-consistent (VPSC) simulation. The predominant activity of non-basal 〈a〉 dislocation slip was revealed by CMWP analysis, and Schmid factor analysis from the EBSD results supported the higher potential of non-basal dislocation slip in comparison with basal 〈a〉 dislocation slip. Moreover, the relative slip activities obtained by the VPSC simulation also show a similar trend to those obtained from the CMWP evaluation.urn:issn:1600-5775text/htmlThe convolutional multiple whole profile fitting method of X-ray line profile analysis using synchrotron radiation allows the experimental determination of dislocation densities separately for different Burgers vectors up to a high degree of deformation. Its reliability for Mg–Zn–Y alloys, in terms of the dislocation activity during tensile deformation, has been successfully verified by combined analysis with electron backscatter diffraction investigation and visco-plastic self-consistent simulation.2023-05-11DISLOCATION; SLIP ACTIVITY; SYNCHROTRON RADIATION; TENSILE TEST; MAGNESIUM ALLOYAnalysis of the dislocation activity of Mg–Zn–Y alloy using synchrotron radiation under tensile loadingInternational Union of CrystallographyHa, C.Kim, Y.M.Woo, S.K.Maawad, E.Letzig, D.Yi, S.doi:10.1107/S1600577523003491enhttps://creativecommons.org/licenses/by/4.0/1600-57752023-05-11med@iucr.orgJuly 202330Journal of Synchrotron Radiation7451600-5775739research papershttps://creativecommons.org/licenses/by/4.0/4FlexPES: a versatile soft X-ray beamline at MAX IV Laboratory
http://scripts.iucr.org/cgi-bin/paper?ok5091
FlexPES is a soft X-ray beamline on the 1.5 GeV storage ring at MAX IV Laboratory, Sweden, providing horizontally polarized radiation in the 40–1500 eV photon energy range and specializing in high-resolution photoelectron spectroscopy, fast X-ray absorption spectroscopy and electron–ion/ion–ion coincidence techniques. The beamline is split into two branches currently serving three endstations, with a possibility of adding a fourth station at a free port. The refocusing optics provides two focal points on each branch, and enables either focused or defocused beam on the sample. The endstation EA01 at branch A (Surface and Materials Science) is dedicated to surface- and materials-science experiments on solid samples at ultra-high vacuum. It is well suited not only to all flavours of photoelectron spectroscopy but also to fast (down to sub-minute) high-resolution X-ray absorption measurements with various detectors. Branch B (Low-Density Matter Science) has the possibility to study gas-phase/liquid samples at elevated pressures. The first endstation of this branch, EB01, is a mobile setup for various ion–ion and electron–ion coincidence techniques. It houses a versatile reaction microscope, which can be used for experiments during single-bunch or multi-bunch delivery. The second endstation, EB02, is based on a rotatable chamber with an electron spectrometer for photoelectron spectroscopy studies on primarily volatile targets, and a number of peripheral setups for sample delivery, such as molecular/cluster beams, metal/semiconductor nanoparticle beams and liquid jets. This station can also be used for non-UHV photoemission studies on solid samples. In this paper, the optical layout and the present performance of the beamline and all its endstations are reported.textFlexPES is a soft X-ray beamline on the 1.5 GeV storage ring at MAX IV Laboratory, Sweden, providing horizontally polarized radiation in the 40–1500 eV photon energy range and specializing in high-resolution photoelectron spectroscopy, fast X-ray absorption spectroscopy and electron–ion/ion–ion coincidence techniques. The beamline is split into two branches currently serving three endstations, with a possibility of adding a fourth station at a free port. The refocusing optics provides two focal points on each branch, and enables either focused or defocused beam on the sample. The endstation EA01 at branch A (Surface and Materials Science) is dedicated to surface- and materials-science experiments on solid samples at ultra-high vacuum. It is well suited not only to all flavours of photoelectron spectroscopy but also to fast (down to sub-minute) high-resolution X-ray absorption measurements with various detectors. Branch B (Low-Density Matter Science) has the possibility to study gas-phase/liquid samples at elevated pressures. The first endstation of this branch, EB01, is a mobile setup for various ion–ion and electron–ion coincidence techniques. It houses a versatile reaction microscope, which can be used for experiments during single-bunch or multi-bunch delivery. The second endstation, EB02, is based on a rotatable chamber with an electron spectrometer for photoelectron spectroscopy studies on primarily volatile targets, and a number of peripheral setups for sample delivery, such as molecular/cluster beams, metal/semiconductor nanoparticle beams and liquid jets. This station can also be used for non-UHV photoemission studies on solid samples. In this paper, the optical layout and the present performance of the beamline and all its endstations are reported.urn:issn:1600-5775text/htmlA new versatile beamline for experiments with soft X-ray absorption, photoelectron emission and electron–ion coincidence spectroscopies is available at MAX IV Laboratory, Sweden, serving user communities from ultra-high-vacuum surface science to materials science and low-density matter research.2023-05-09PHOTOELECTRON SPECTROSCOPY; NEXAFS; MULTI-COINCIDENCE; SOFT X-RAYSFlexPES: a versatile soft X-ray beamline at MAX IV LaboratoryInternational Union of CrystallographyPreobrajenski, A.Generalov, A.Öhrwall, G.Tchaplyguine, M.Tarawneh, H.Appelfeller, S.Frampton, E.Walsh, N.doi:10.1107/S1600577523003429enhttps://creativecommons.org/licenses/by/4.0/4https://creativecommons.org/licenses/by/4.0/831beamlines1600-5775July 202384030Journal of Synchrotron Radiationmed@iucr.org1600-57752023-05-09Soft X-ray spectro-ptychography of boron nitride nanobamboos, carbon nanotubes and permalloy nanorods
http://scripts.iucr.org/cgi-bin/paper?mo5266
Spectro-ptychography offers improved spatial resolution and additional phase spectral information relative to that provided by scanning transmission X-ray microscopes. However, carrying out ptychography at the lower range of soft X-ray energies (e.g. below 200 eV to 600 eV) on samples with weakly scattering signals can be challenging. Here, results of soft X-ray spectro-ptychography at energies as low as 180 eV are presented, and its capabilities are illustrated with results from permalloy nanorods (Fe 2p), carbon nanotubes (C 1s) and boron nitride bamboo nanostructures (B 1s, N 1s). The optimization of low-energy X-ray spectro-ptychography is described and important challenges associated with measurement approaches, reconstruction algorithms and their effects on the reconstructed images are discussed. A method for evaluating the increase in radiation dose when using overlapping sampling is presented.textSpectro-ptychography offers improved spatial resolution and additional phase spectral information relative to that provided by scanning transmission X-ray microscopes. However, carrying out ptychography at the lower range of soft X-ray energies (e.g. below 200 eV to 600 eV) on samples with weakly scattering signals can be challenging. Here, results of soft X-ray spectro-ptychography at energies as low as 180 eV are presented, and its capabilities are illustrated with results from permalloy nanorods (Fe 2p), carbon nanotubes (C 1s) and boron nitride bamboo nanostructures (B 1s, N 1s). The optimization of low-energy X-ray spectro-ptychography is described and important challenges associated with measurement approaches, reconstruction algorithms and their effects on the reconstructed images are discussed. A method for evaluating the increase in radiation dose when using overlapping sampling is presented.urn:issn:1600-5775text/htmlFirst B-edge (192 eV) soft X-ray ptychography, challenges related to weak scattering, measurement approaches and reconstructions in energies as low as 180 eV are discussed.2023-05-05SOFT X-RAY PTYCHOGRAPHY; PTYCHOGRAPHY RECONSTRUCTION; NANOSTRUCTURES; NANOMATERIALSSoft X-ray spectro-ptychography of boron nitride nanobamboos, carbon nanotubes and permalloy nanorodsInternational Union of CrystallographyVijayakumar, J.Yuan, H.Mille, N.Stanescu, S.Swaraj, S.Favre-Nicolin, V.Najafi, E.Hitchcock, A.P.Belkhou, R.doi:10.1107/S1600577523003399enhttps://creativecommons.org/licenses/by/4.0/July 2023Journal of Synchrotron Radiation301600-57752023-05-05med@iucr.orgresearch papershttps://creativecommons.org/licenses/by/4.0/41600-5775Full-field hard X-ray nano-tomography at SSRF
http://scripts.iucr.org/cgi-bin/paper?ay5614
An in-house designed transmission X-ray microscopy (TXM) instrument has been developed and commissioned at beamline BL18B of the Shanghai Synchrotron Radiation Facility (SSRF). BL18B is a hard (5–14 keV) X-ray bending-magnet beamline recently built with sub-20 nm spatial resolution in TXM. There are two kinds of resolution mode: one based on using a high-resolution-based scintillator-lens-coupled camera, and the other on using a medium-resolution-based X-ray sCMOS camera. Here, a demonstration of full-field hard X-ray nano-tomography for high-Z material samples (e.g. Au particles, battery particles) and low-Z material samples (e.g. SiO2 powders) is presented for both resolution modes. Sub-50 nm to 100 nm resolution in three dimensions (3D) has been achieved. These results represent the ability of 3D non-destructive characterization with nano-scale spatial resolution for scientific applications in many research fields.textAn in-house designed transmission X-ray microscopy (TXM) instrument has been developed and commissioned at beamline BL18B of the Shanghai Synchrotron Radiation Facility (SSRF). BL18B is a hard (5–14 keV) X-ray bending-magnet beamline recently built with sub-20 nm spatial resolution in TXM. There are two kinds of resolution mode: one based on using a high-resolution-based scintillator-lens-coupled camera, and the other on using a medium-resolution-based X-ray sCMOS camera. Here, a demonstration of full-field hard X-ray nano-tomography for high-Z material samples (e.g. Au particles, battery particles) and low-Z material samples (e.g. SiO2 powders) is presented for both resolution modes. Sub-50 nm to 100 nm resolution in three dimensions (3D) has been achieved. These results represent the ability of 3D non-destructive characterization with nano-scale spatial resolution for scientific applications in many research fields.urn:issn:1600-5775text/htmlA demonstration of full-field hard X-ray nano-tomography for high- and low-Z material samples is presented for the two TXM resolution modes developed at beamline BL18B at SSRF.2023-05-05X-RAY NANO-IMAGING; ELLIPSOIDAL CAPILLARY; SYNCHROTRON RADIATION FACILITY; SPATIAL RESOLUTIONFull-field hard X-ray nano-tomography at SSRFInternational Union of CrystallographyTao, F.Wang, J.Du, G.Su, B.Zhang, L.Hou, C.Deng, B.Xiao, T.doi:10.1107/S1600577523003168enhttps://creativecommons.org/licenses/by/4.0/beamlineshttps://creativecommons.org/licenses/by/4.0/41600-5775Journal of Synchrotron Radiation30July 20232023-05-051600-5775med@iucr.orgA von Hámos spectrometer for diamond anvil cell experiments at the High Energy Density Instrument of the European X-ray Free-Electron Laser
http://scripts.iucr.org/cgi-bin/paper?ok5088
A von Hámos spectrometer has been implemented in the vacuum interaction chamber 1 of the High Energy Density instrument at the European X-ray Free-Electron Laser facility. This setup is dedicated, but not necessarily limited, to X-ray spectroscopy measurements of samples exposed to static compression using a diamond anvil cell. Si and Ge analyser crystals with different orientations are available for this setup, covering the hard X-ray energy regime with a sub-eV energy resolution. The setup was commissioned by measuring various emission spectra of free-standing metal foils and oxide samples in the energy range between 6 and 11 keV as well as low momentum-transfer inelastic X-ray scattering from a diamond sample. Its capabilities to study samples at extreme pressures and temperatures have been demonstrated by measuring the electronic spin-state changes of (Fe0.5Mg0.5)O, contained in a diamond anvil cell and pressurized to 100 GPa, via monitoring the Fe Kβ fluorescence with a set of four Si(531) analyser crystals at close to melting temperatures. The efficiency and signal-to-noise ratio of the spectrometer enables valence-to-core emission signals to be studied and single pulse X-ray emission from samples in a diamond anvil cell to be measured, opening new perspectives for spectroscopy in extreme conditions research.textA von Hámos spectrometer has been implemented in the vacuum interaction chamber 1 of the High Energy Density instrument at the European X-ray Free-Electron Laser facility. This setup is dedicated, but not necessarily limited, to X-ray spectroscopy measurements of samples exposed to static compression using a diamond anvil cell. Si and Ge analyser crystals with different orientations are available for this setup, covering the hard X-ray energy regime with a sub-eV energy resolution. The setup was commissioned by measuring various emission spectra of free-standing metal foils and oxide samples in the energy range between 6 and 11 keV as well as low momentum-transfer inelastic X-ray scattering from a diamond sample. Its capabilities to study samples at extreme pressures and temperatures have been demonstrated by measuring the electronic spin-state changes of (Fe0.5Mg0.5)O, contained in a diamond anvil cell and pressurized to 100 GPa, via monitoring the Fe Kβ fluorescence with a set of four Si(531) analyser crystals at close to melting temperatures. The efficiency and signal-to-noise ratio of the spectrometer enables valence-to-core emission signals to be studied and single pulse X-ray emission from samples in a diamond anvil cell to be measured, opening new perspectives for spectroscopy in extreme conditions research.urn:issn:1600-5775text/htmlThe implementation of a von Hámos spectrometer for diamond anvil cell experiments at the High Energy Density Instrument of the EuXFEL is described.2023-05-09X-RAY SPECTROSCOPY; X-RAY DIFFRACTION; INELASTIC X-RAY SCATTERING; DIAMOND ANVIL CELL; SPECTROMETERS; IMAGING SPECTROSCOPY; X-RAY DETECTORSA von Hámos spectrometer for diamond anvil cell experiments at the High Energy Density Instrument of the European X-ray Free-Electron LaserInternational Union of CrystallographyKaa, J.M.Konôpková, Z.Preston, T.R.Cerantola, V.Sahle, C.J.Förster, M.Albers, C.Libon, L.Sakrowski, R.Wollenweber, L.Buakor, K.Dwivedi, A.Mishchenko, M.Nakatsutsumi, M.Plückthun, C.Schwinkendorf, J.-P.Spiekermann, G.Thiering, N.Petitgirard, S.Tolan, M.Wilke, M.Zastrau, U.Appel, K.Sternemann, C.doi:10.1107/S1600577523003041enhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/822beamlinesmed@iucr.org2023-05-091600-577583030Journal of Synchrotron RadiationJuly 2023Harmonic radiation contribution and X-ray transmission at the Small Quantum Systems instrument of European XFEL
http://scripts.iucr.org/cgi-bin/paper?ve5167
Transmission measurements of the soft X-ray beamline to the Small Quantum Systems (SQS) scientific instrument at the SASE3 undulator of European XFEL are presented. Measurements are reported for a wide range of photon energies (650 eV to 2400 eV), using X-ray gas monitors as well as a bolometric radiometer. The results are in good agreement with simulations for the beam transport and show a transmission of up to 80% over the whole photon energy range. The contribution of second- and third-harmonic radiation of the soft X-ray undulator is determined at selected photon energies by performing transmission measurements using a gas absorber to provide variable attenuation of the incoming photon flux. A comparison of the results with semi-analytic calculations for the generation of free-electron laser pulses in the SASE3 undulator reveals an influence of apertures along the beam transport on the exact harmonic content to be accounted for at the experiment. The second-harmonic content is measured to be in the range of 0.1% to 0.3%, while the third-harmonic contributed a few percent to the SASE3 emission. For experiments at the SQS instrument, these numbers can be reduced through specific selections of the mirror reflection angles.textTransmission measurements of the soft X-ray beamline to the Small Quantum Systems (SQS) scientific instrument at the SASE3 undulator of European XFEL are presented. Measurements are reported for a wide range of photon energies (650 eV to 2400 eV), using X-ray gas monitors as well as a bolometric radiometer. The results are in good agreement with simulations for the beam transport and show a transmission of up to 80% over the whole photon energy range. The contribution of second- and third-harmonic radiation of the soft X-ray undulator is determined at selected photon energies by performing transmission measurements using a gas absorber to provide variable attenuation of the incoming photon flux. A comparison of the results with semi-analytic calculations for the generation of free-electron laser pulses in the SASE3 undulator reveals an influence of apertures along the beam transport on the exact harmonic content to be accounted for at the experiment. The second-harmonic content is measured to be in the range of 0.1% to 0.3%, while the third-harmonic contributed a few percent to the SASE3 emission. For experiments at the SQS instrument, these numbers can be reduced through specific selections of the mirror reflection angles.urn:issn:1600-5775text/htmlMeasurements of the transmission as well as the contribution of harmonic radiation at the soft X-ray beamline of the Small Quantum Systems instrument at the SASE3 undulator of European XFEL are presented.2023-05-10FREE-ELECTRON LASERS; X-RAY BEAM TRANSPORT; HARMONIC RADIATION; ATOMIC, MOLECULAR AND OPTICAL SCIENCEHarmonic radiation contribution and X-ray transmission at the Small Quantum Systems instrument of European XFELInternational Union of CrystallographyBaumann, T.M.Boll, R.De Fanis, A.Grychtol, P.Ilchen, M.Jastrow, U.F.Kato, M.Lechner, C.Maltezopoulos, T.Mazza, T.Montaño, J.Music, V.Ovcharenko, Y.Rennhack, N.Rivas, D.E.Saito, N.Schmidt, P.Serkez, S.Sorokin, A.Usenko, S.Yan, J.Geloni, G.Tanaka, T.Tiedtke, K.Meyer, M.doi:10.1107/S1600577523003090enhttps://creativecommons.org/licenses/by/4.0/research papers6624https://creativecommons.org/licenses/by/4.0/1600-5775July 2023670Journal of Synchrotron Radiation301600-57752023-05-10med@iucr.orgDevelopment of a custom-made 2.8 T permanent-magnet dipole photon source for the ROCK beamline at SOLEIL
http://scripts.iucr.org/cgi-bin/paper?rv5172
In August 2021, the SOLEIL storage ring was restarted after the summer shutdown with a new bending magnet made entirely of permanent magnets. Producing a magnetic field of 2.8 T, it replaced one of the 32 electromagnetic dipoles (magnetic field of 1.7 T) of the ring to allow the ROCK beamline to exploit more intense photon fluxes in the hard X-ray range, thus improving the time resolution performances of the beamline for experiments carried out above 20 keV. The reduction of the new dipole magnetic gap required to produce the higher field has led to the construction and installation of a new vacuum vessel. The realization of the new dipole with permanent magnets was a technological feat due to the very strong magnetic forces. The permanent-magnet assembly required dedicated tools to be designed and constructed. Thanks to accurate magnetic measurements, a precise modelization of the new dipole was performed to identify its effects on the electron beam dynamics. The first measurements carried out on the ROCK beamline have highlighted the expected increase in photon flux, and the operation performances remain unchanged for the other beamlines. Here, the major developments and results of this innovative project are described in terms of technology, electron beam dynamics and photon beam performance on the ROCK beamline.textIn August 2021, the SOLEIL storage ring was restarted after the summer shutdown with a new bending magnet made entirely of permanent magnets. Producing a magnetic field of 2.8 T, it replaced one of the 32 electromagnetic dipoles (magnetic field of 1.7 T) of the ring to allow the ROCK beamline to exploit more intense photon fluxes in the hard X-ray range, thus improving the time resolution performances of the beamline for experiments carried out above 20 keV. The reduction of the new dipole magnetic gap required to produce the higher field has led to the construction and installation of a new vacuum vessel. The realization of the new dipole with permanent magnets was a technological feat due to the very strong magnetic forces. The permanent-magnet assembly required dedicated tools to be designed and constructed. Thanks to accurate magnetic measurements, a precise modelization of the new dipole was performed to identify its effects on the electron beam dynamics. The first measurements carried out on the ROCK beamline have highlighted the expected increase in photon flux, and the operation performances remain unchanged for the other beamlines. Here, the major developments and results of this innovative project are described in terms of technology, electron beam dynamics and photon beam performance on the ROCK beamline.urn:issn:1600-5775text/htmlSince August 2021, the French synchrotron light source SOLEIL has been running with a 1 m-long permanent-magnet dipole producing a magnetic field of 2.8 T. This is a major modification of the storage ring that allows the high-energy photon flux for the ROCK beamline to be increased and significantly improves the resolution for experiments performed above 20 keV.2023-05-10SOLEIL; SYNCHROTRON LIGHT SOURCE; PERMANENT MAGNET DIPOLE; ROCK PHOTON BEAMLINEDevelopment of a custom-made 2.8 T permanent-magnet dipole photon source for the ROCK beamline at SOLEILInternational Union of CrystallographyBrunelle, P.Béchu, N.Briois, V.Marteau, F.Ribbens, M.Berteaud, P.Delétoille, X.Dupuy, E.Herbeaux, C.Labat, M.Lestrade, A.Nadji, A.Nadolski, L.Nouna, M.Pruvost, J.-B.doi:10.1107/S1600577523002990enhttps://creativecommons.org/licenses/by/4.0/1600-57754https://creativecommons.org/licenses/by/4.0/research papers695med@iucr.org1600-57752023-05-10July 2023707Journal of Synchrotron Radiation30Photocatalytic setup for in situ and operando ambient-pressure X-ray photoelectron spectroscopy at MAX IV Laboratory
http://scripts.iucr.org/cgi-bin/paper?ve5168
The Ambient-Pressure X-ray Photoelectron Spectroscopy (APXPS) endstation at the SPECIES beamline at MAX IV Laboratory has been improved. The latest upgrades help in performing photo-assisted experiments under operando conditions in the mbar pressure range using gas and vapour mixtures whilst also reducing beam damage to the sample caused by X-ray irradiation. This article reports on endstation upgrades for APXPS and examples of scientific cases of in situ photocatalysis, photoreduction and photo-assisted atomic layer deposition (photo-ALD).textThe Ambient-Pressure X-ray Photoelectron Spectroscopy (APXPS) endstation at the SPECIES beamline at MAX IV Laboratory has been improved. The latest upgrades help in performing photo-assisted experiments under operando conditions in the mbar pressure range using gas and vapour mixtures whilst also reducing beam damage to the sample caused by X-ray irradiation. This article reports on endstation upgrades for APXPS and examples of scientific cases of in situ photocatalysis, photoreduction and photo-assisted atomic layer deposition (photo-ALD).urn:issn:1600-5775text/htmlA new experimental setup makes it possible to follow the evolution of surfaces in situ with ambient-pressure X-ray photoelectron spectroscopy by simultaneously irradiating the sample with ultra-violet and visible light. Photo-assisted processes can be carried out close to industrially relevant conditions.2023-04-17PHOTOCATALYSIS; APXPS; PHOTO-ALD; SOLAR SIMULATORPhotocatalytic setup for in situ and operando ambient-pressure X-ray photoelectron spectroscopy at MAX IV LaboratoryInternational Union of CrystallographyKlyushin, A.Ghosalya, M.Kokkonen, E.Eads, C.Jones, R.Nalajala, N.Gopinath, C.S.Urpelainen, S.doi:10.1107/S1600577523002801enhttps://creativecommons.org/licenses/by/4.0/https://creativecommons.org/licenses/by/4.0/3research papers6131600-577530Journal of Synchrotron Radiation619May 2023med@iucr.org2023-04-171600-5775Assessing an aqueous flow cell designed for in situ crystal growth under X-ray nanotomography and effects of radiolysis products
http://scripts.iucr.org/cgi-bin/paper?vy5005
Nucleation and growth of minerals has broad implications in the geological, environmental and materials sciences. Recent developments in fast X-ray nanotomography have enabled imaging of crystal growth in solutions in situ with a resolution of tens of nanometres, far surpassing optical microscopy. Here, a low-cost, custom-designed aqueous flow cell dedicated to the study of heterogeneous nucleation and growth of minerals in aqueous environments is shown. To gauge the effects of radiation damage from the imaging process on growth reactions, radiation-induced morphological changes of barite crystals (hundreds of nanometres to ∼1 µm) that were pre-deposited on the wall of the flow cell were investigated. Under flowing solution, minor to major crystal dissolution was observed when the tomography scan frequency was increased from every 30 min to every 5 min (with a 1 min scan duration). The production of reactive radicals from X-ray induced water radiolysis and decrease of pH close to the surface of barite are likely responsible for the observed dissolution. The flow cell shown here can possibly be adopted to study a wide range of other chemical reactions in solutions beyond crystal nucleation and growth where the combination of fast flow and fast scan can be used to mitigate the radiation effects.textNucleation and growth of minerals has broad implications in the geological, environmental and materials sciences. Recent developments in fast X-ray nanotomography have enabled imaging of crystal growth in solutions in situ with a resolution of tens of nanometres, far surpassing optical microscopy. Here, a low-cost, custom-designed aqueous flow cell dedicated to the study of heterogeneous nucleation and growth of minerals in aqueous environments is shown. To gauge the effects of radiation damage from the imaging process on growth reactions, radiation-induced morphological changes of barite crystals (hundreds of nanometres to ∼1 µm) that were pre-deposited on the wall of the flow cell were investigated. Under flowing solution, minor to major crystal dissolution was observed when the tomography scan frequency was increased from every 30 min to every 5 min (with a 1 min scan duration). The production of reactive radicals from X-ray induced water radiolysis and decrease of pH close to the surface of barite are likely responsible for the observed dissolution. The flow cell shown here can possibly be adopted to study a wide range of other chemical reactions in solutions beyond crystal nucleation and growth where the combination of fast flow and fast scan can be used to mitigate the radiation effects.urn:issn:1600-5775text/htmlFast flow and fast imaging can reduce radiation damage in an X-ray nanotomography cell designed for studying mineral nucleation and growth in solutions.2023-04-17X-RAY NANOTOMOGRAPHY; RADIOLYSIS; CRYSTAL GROWTH; NUCLEATIONAssessing an aqueous flow cell designed for in situ crystal growth under X-ray nanotomography and effects of radiolysis productsInternational Union of CrystallographyYuan, K.Starchenko, V.Rampal, N.Yang, F.Xiao, X.Stack, A.G.doi:10.1107/S1600577523002783enhttps://creativecommons.org/licenses/by/4.0/2023-04-171600-5775med@iucr.org642Journal of Synchrotron Radiation30May 20231600-5775research papers6343https://creativecommons.org/licenses/by/4.0/