Design Study of a Time of Flight Small-Angle Diffractometer for a Pulsed Neutron Source

摘要

The design study for a neutron SAS instrument at Argonne's proposed Intense Pulsed Neutron Source (peak thermal neutron flux 10 exp 16 n/cm exp 2 -sec) indicates that an effective high-resolution TOF SAS diffractometer can be constructed. The design features include a converging slit collimator, provision for 5 x 5 cm exp 2 sample cross sectional area, and a 1 x 1 m exp 2 , two-dimensional detector. The fractional wavelength resolution of the instrument is negligibly small for all wavelengths. The resolution was computed by Monte Carlo simulation and is constant over most of the Q range. A special feature of the instrument is the wide range of accessible Q's, without the requirement of instrument configurational changes. The flux on sample exceeds that at conventional reactor instruments of comparable resolution. (ERA citation 03:024974)