A simulation of the indirect TOF geometry part of the OSIRIS instrument.
Author: Peter Christiansen with input from Mark Telling, updates by P Willendrup
Origin: DTU Fysik, RISOE and ISIS
Date: November 2015
If LAMBDA = 0, the choppers are disabled, else the choppers are
centered to chop around this wavelength and the source is studied in the
interval LAMBDA +- DLAMBDA.
1) Monchromator is not realistic in the sense that it does NOT
smear the beam out according to the mosaicity, only does the N=1
reflection, and the d-spread is handled in a simple way
2) The instrument is not validated or certified by ISIS. Is only put in
McStas for completeness.
Parameters in boldface are required;
the others are optional.
Central wavelength of source and chopper wavelength