he Tender Energy Spectroscopy Beamline at SSRF

he tender energy spectroscopy beamline (BL16U1) is one of the phase-II beamline at the Shanghai Synchrotron Radiation Facility (SSRF). The design and performance of the tender energy spectroscopy beamline at SSRF are described in this paper. Based on a 26 mm-period in vacuum undulator (IVU) source, the beamline is to give an operable energy range between 2.1 and 16 keV, covering the K-edges of those elements from P to Rb and the L3-edges of those elements from Zr to Bi. The principal optical elements of the beamline consist of a toroidal mirror, a liquid-nitrogen cooled double-crystal monochromator, a high harmonic rejection mirror and two pairs of Kirkpatrick–Baez (KB) mirrors. Three end-stations, including the non-focusing, microprobe and sub-microprobe end-stations, are installed on the beamline. X-ray fluorescence (XRF), X-ray absorption spectroscopy (XAS) including X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS), have been achieved under vacuum or He atmosphere at the non-focusing end-station with a spot size of ~ 670×710 μm2. Based on two KB mirrors systems, micro-X-ray fluorescence (μXRF) mapping studies and micro-X-ray absorption near-edge structure (μXANES) will be operated with a spot size of nearly ~ 3.3×1.3 μm2 at the microprobe end-station, and with a smaller spot size of ~ 0.5×0.25 μm2 at the sub-microprobe end-station. Up to now, the non-focusing end-station of the BL16U1 is officially opened to users in Jan. 2024. The microprobe and sub-microprobe end-stations will be opened to users in the near future. This paper describes the characteristics, short-term technical developments and a few of the early experimental results of this new beamline.