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.本数据集包含两组在不同束流条件下采集的衍射图像。该衍射图像采集于上海同步辐射光源（Shanghai Synchrotron Radiation Facility）BL15U线站，光子能量为10 keV。该线站采用一对柯克帕特里克-贝兹（Kirkpatrick-Baez，KB）镜进行束流聚焦，通过刃边扫描法测得的聚焦光斑尺寸约为4 × 4 μm²。为提升束流相干性，次级源孔径设为200 × 30 μm²。实验前，该KB镜已于线站处通过硅基底完成预校准，其曲率可通过两根弯曲杆进行调节。通过调节KB镜的俯仰角与曲率，在不同校准参数下，分别采集了焦斑附近放置与未放置薄砂纸时的衍射图像。数据采集系统由显微镜物镜系统（Optique Peter）与互补金属氧化物半导体（CMOS）相机（Hamamatsu）耦合组成，该系统放置于焦斑下游2075 mm处。采集图像的像素尺寸为1.625 μm，单张图像分辨率为2048 × 2048。