An improved integration method in serial femtosecond crystallography

Recent experiments in serial femtosecond crystallography (SFX) have demonstrated the feasibility of obtaining structural information from nanoscale crystals using X-ray free-electron lasers (XFELs). However, millions of crystals are required to determine one reliable structure. Here, an improved integration algorithm for SFX data processing is reported. By evaluating the dimensions of each crystal and correcting for the geometric factors of single patterns, the effective diffraction intensities, as opposed to the directly measured single-shot pattern diffraction intensities, can be merged to acquire more accurate integrated intensities which can be used for structure determination. This improvement enhances the quality of electron-density maps and decreases the number of diffraction patterns that are needed to solve the crystal structure in SFX experiments.