Pink-Beam Small-Angle X-ray Scattering Beamline at the Extremely Brilliant High Energy Photon Source
Yunpeng Liu, Guang Mo, Chenxi Yang, Zhaoqiang Cui, Zongyang Yue, Zina Ou, Ye Tian, Fugui Yang, Xueqing Xing, Zhongjun Chen, Quanjie Jia, Ming Li, Zhihong Li, Zhonghua WuAbstract
The construction of the pink-beam small-angle X-ray scattering (SAXS) beamline, ID08, was completed at the High Energy Photon Source (HEPS) in 2025. To enable fast time-resolved scattering experiments, the ID08 beamline employs a pink X-ray beam as the fundamental photon source, which is emitted from an in-air planar undulator. The pink-beam exhibits an energy resolution of 0.95%, with a photon flux up to 3.2 × 1015 phs/s/0.1%bw@12 keV@200 mA and an energy coverage of 8–12 keV. The beam size at the sample position can be varied from 0.2 mm × 0.2 mm to 0.5 mm × 0.5 mm (H×V) using the primary slits. With the current beamline layout, the accessible q-range for SAXS measurement is 0.0105–6.68 nm–1, corresponding to a detectable particle size range of 1–600 nm. Coupled with three advanced pixel-array detectors and optical components installed at a later stage, such as compound refractive lens (CRL), this beamline enables not only millisecond-level time-resolved individual SAXS, wide-angle X-ray scattering (WAXS), and ultrasmall-angle X-ray scattering (USAXS) experiments but also simultaneous combined WAXS/SAXS/USAXS measurement. The HEPS-ID08 beamline supports both static and dynamic characterization of various material systems across length scales from angstrom down to submicron, opening up new avenues for structural investigations into non-equilibrium and time-dependent processes in materials.