Detected diffraction pattern at Shanghai Synchrotron Radiation Beamline15U with different alignment parameters of Kirkpatrick–Baez focusing mirror

This dataset contains two sets of diffraction images acquired at different beam conditions. The diffaction images were collected at the beamline BL15U of the Shanghai Synchrotron Radiation Facility with a photon energy of 10 keV. The beamline uses a pair of Kirkpatrick-Baez (KB) mirrors to focus the beam. The focus spot size was about 4 × 4 μm2 measured by knife-edge scan method. The secondary source aperture was 200 × 30 μm2 for improving the beam coherence. The KB mirrors were pre-aligned with a silicon substrate at the beamline before the experiment, and its curvature can be adjusted by two bending rods. Adjusting the pitch angle and curvature of KB mirrors, diffraction images were collected with and without a thin sandpaper placed near the focus at different alignment parameters. The data was collected by a microscope objective lens system (Optique Peter) coupled to a complementary metal-oxide semiconductor (CMOS) camera (Hamamatsu), which was placed 2075 mm downstream from the focus. Pixel size of collected images is 1.625 μm and each image is 2048 × 2048 size.