Hirofumi Morikawa

A triple-axis/four-circle diffractometer at the beam line BL-3A of the photon factory

A triple‐axis/four‐circle diffractometer was newly designed and installed in the experimental station BL‐3A of the Photon Factory. The station is currently used for multipurpose works such as diffraction, scattering, and absorption in the x‐ray region both for basic and applied research. The diffractometer consists of three different types of goniometers: (1) a four‐circle goniometer having a high‐precision ω axis and a large, off‐centered χ circle to mount various apparatuses such as an electric furnace and a helium cryostat; (2) a two‐circle goniometer for crystal analyzers; and (3) a two‐circle goniometer for collimators. ‘‘Dynamic’’ studies at high temperatures and microarea diffraction studies are possible by using a highly focused x‐ray beam provided by a mirror‐monochromator system in BL‐3A. Furthermore, the combination of the high precision diffractometer and the well‐collimated beam makes possible such experiments as high energy and/or momentum resolution measurements, ultrasmall angle scattering...