A SAXS/WAXD beamline with laboratory SAXS apparatus at NanoTerasu.

NanoTerasu is a new 3 GeV synchrotron radiation facility in Sendai, Japan, which began user operation in April 2024. A station for small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) has been built at the wiggler beamline BL08W. The station was built in a branch for which an X-ray beam is provided by Bragg reflection from two Si crystals. The X-ray energy is 8.0 or 13.1 keV using either an Si(111) or an Si(220) crystal, respectively. The beam is focused with an Ru-coated bent cylindrical mirror. In the SAXS station, an Anton Paar SAXSpoint 5.0 laboratory X-ray apparatus has been installed. The original X-ray generator and focusing mirror in the laboratory equipment were removed and four-quadrant slits and an ion chamber have been installed. Low-scatter slits in SAXSpoint 5.0 are used as guard slits in front of the sample. The X-ray detector is a DECTRIS Eiger2 1M. The slits, sample and detector are enclosed in a vacuum chamber to reduce scattering from the air. The detector can be moved along the X-ray axis under vacuum to change the sample-to-detector distance between 53 and 1610 mm. The X-ray flux at 8.0 keV is 1.0 × 10¹¹ cps with a ring current of 200 mA, shortening the exposure time by nearly 1000 times compared with the original laboratory X-ray source. The purpose of employing SAXSpoint 5.0 is to provide a user-friendly SAXS/WAXD system. Anton Paar's measurement control system is employed in user operations. Many users utilize a multi-sample holder onto which 20 samples are fixed and measured in turn as programmed. The data analysis software is also provided by Anton Paar, but data can optionally be stored in TIFF format to be processed by any software that users are familiar with. Among the various sample attachments available from Anton Paar, a goniometer stage for grazing-incidence SAXS/WAXD is employed by many users.