Small-angle neutron scattering instrument of institute for solid state physics, the University of Tokyo (SANS-U) and its application to biology.

A small-angle neutron spectrometer (SANS-U) suitable for the study of mesoscopic structure in the field of polymer chemistry and biology, has been constructed at the guide hall of JRR-3M reactor at the Japan Atomic Energy Research Institute. The instrument is 32m long and utilizes a mechanical velocity selector and pinhole collimation to provide a continuous beam with variable wavelength in the range from 5 to 10 A. The neutron detector is a 65 x 65 cm2 2D position sensitive proportional counter. The practical Q range of SANS-U is 0.0008 to 0.45 A-1. The design, characteristics and performance of SANS-U are described with some biological studies using SANS-U.