Figure 3
Properties of the BMIT-ID beam. Shown in (a) is the photon flux density through the centered 1 mm × 1 mm aperture at a distance of 58 m from the source: curves show spectral flux density (computed in SPECTRA10) of the beam attenuated by the mandatory filters and 4.4 mm of Si (combined thickness of the two monochromator crystals); flux densities at 2.5 T and 3.7 T and with the same sets of attenuators were measured with the radiometer and computed in XRT and are shown by squares and stars, respectively. Panel (b) shows the vertical profile of the monochromatic beam while panel (c) presents the rocking curve of the second monochromator crystal. In both cases the X-ray energy was 50 keV and a detector with 8 µm × 8 µm pixels was used to acquire the data; in both (b) and (c) blue solid lines are experimental values while dotted red lines were simulated in XRT (see text for details). |