The time-of-flight small-angle scattering spectrometer SAN at the KENS pulsed cold neutron source

This paper describes the configuration and performance of a new time-of-flight (TOF) small-angle neutron scattering spectrometer SAN installed at the pulsed cold neutron source (KENS) at the National Laboratory for High Energy Physics (KEK). The spectrometer has advantages over conventional small-angle scattering apparatus: one is its capability for simultaneous measurements over a wide Q range (0.003 ≤ Q ≤ 4 Å⁻¹) and another is the new information that it provides by exploiting the wavelength dependence of the scattering. For example, the inelastic and elastic scattering can be separated without performing an energy analysis. The design principles of this type of spectrometer are also discussed.