Description
ABSTRACT:
The NCNR is currently designing a new cold neutron crystal spectrometer, QMS, to replace the SPINS cold triple axis on the NG-5 beamline. The primary spectrometer before the sample consists of an elliptical guide and double focusing monochromator that hosts a velocity selector, V-cavity supermirror polarizer, resolution masks, and fast neutron filter within the incident beam. The guide and monochromator instrument parameters were globally optimized via McStas to maximize the flux at the sample position. Additional McStas studies were then employed to optimize the design and placement of the remaining devices. In all cases, this analysis successfully leveraged the complicated flux profile to improve the performance of each device. This talk will outline the key design elements of each device operating within the incident beam, the strategy employed to optimize these elements, and their expected performance on the QMS instrument.
