The soft X-ray magnetic circular dichroism (XMCD) beamline BL12B is primarily designed for high-energy-resolution and high-signal-to-noise-ratio studies in soft X-ray absorption spectroscopy (sXAS) and circular/linear dichroism spectroscopy (XMCD/XMLD). Currently, this beamline includes two branches, the BL12B-a and BL12B-b. The BL12B-a covers an energy range of 100-1000 eV and has a flux of 5×10E9 phs/s, connected with an octupole vector magnet and an UHV chamber that dedicated to XAS/XMCD/XMLD measurements. The BL12B-b covers an energy from 50 to 1100 eV and has a flux of 1.0x10E10 phs/s and is integrated with a standard XAS measurement chamber and a newly developed in-situ XAS endstation, which is capable of providing several key in-situ or operando conditions such as gas cell, liquid cell, laser heating, bias and light, for the XAS investigation of real chemical reactions. The spot size of both branches is the same as 1x0.5 mm2. Soft X-ray absorption spectroscopy offers element-specific selectivity, enabling the probing of the local atomic structure and electronic environment of absorbing atoms. This facility provides a reliable, stable, and user-friendly experimental platform for the broadest user community. It holds significant value in elucidating the microscopic mechanisms underlying the physicochemical properties of materials and advancing precise control methods for material characteristics. Furthermore, it serves as a robust open research tool for fundamental studies, driving the transition from materials observation science to materials control science and empowering the development of advanced material engineering methodologies.
Parameters：
| Energy Range：50 eV -- 1000 eV | Resolution：2000 @244 eV (E/⊿E) |
| Photon Flux：5×109 phs/s（@244eV，300 mA） | Beam Size：1 mm × 0.5 mm |
| Temperature：10-300 K （XMCD end-station），90K-300K（XAS end-station） | Magnetic field：0-1T （XMCD end-station） |
| Pressure：8×10-8 Pa（XMCD end-station）, 5×10-8 Pa（XAS end-station），5×10-6 Pa（In-situ XAS end-station） | |
Beamline staff：
Yan Wensheng | 0551-63602131 ywsh2000@ustc.edu.cn |
Zhang Wenhua | 0551-63601992-1121 zhangwh@ustc.edu.cn |
| Chen Kai | 18214752842 kaichen2021@ustc.edu.cn |
Li Qian | 0551-63607465 liqian89@ustc.edu.cn |
Chen Shuangming | 0551-63607731 csmp@ustc.edu.cn |
Wang Chao | 0551-63602060 chaowng@ustc.edu.cn |
Hu Fengchun | 0551-63602060 fchu@ustc.edu.cn |
