Abstract: The metrological station "Cosmos" receives radiation from the bending magnet of the storage ring VEPP-4. The station was originally intended for to various kinds of metrological work in soft X-ray and VUV range (10-5000 eV): certification of spectrometers, optical elements, detectors, etc. At present, the station equipped by the dubble-crystal Si(111) monochromator. This upgrade has made it possible to perform spectroscopic measurements in the tendep X-ray range (2-10 keV). In the interests of station users and for the development of procedures the number of measurements of XANES spectra near the K-edges of S, P, Cl, Cu and L-edges of Nb, Mo, Zr were carried out. To expand the spectral range of available energies, a hybrid scheme with long period organic KAP and RbAP crystals paired with a multilayer mirror was developed too. The multilayer mirror has a period close to the lattice parameter of crystals (13.47 and 13 A, respectively) and servants to prevent their radiation damage. It is expected that such an optical scheme will make it possible to expand the spectral range in the soft energy region up to 500 eV, which corresponds to the K edge of oxygen. Сurrently, the XAFS spectroscopy procedure implemented at the station is used by our users for the development of new functional materials. However, the most important thing is the station is considered as prototype for the soft X-ray XAFS station for the new synchrotron source SKIF.

Cite: Nikolenko A. , Fedorenko A. , Syrokvashin M. , Zavertkin P. , Polkovnikov V.
Soft X-ray SR Station «Kosmos» at the VEPP-4 Storage Ring: Status and XAFS Applications
International Conference "Synchrotron and Free electron laser Radiation: generation and application" 27-30 Jun 2022