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McStas: Test_Fermi Instrument at Tests_optics

[ Identification | Description | Input parameters | Output parameters | Links ]

The Test_Fermi Instrument

Cross comparison of Fermi Chopper components


  • Site: Tests_optics
  • Author: E. Farhi []
  • Origin: ILL
  • Date: Sept 1st, 2008
  • Version:(Unknown)


Cross comparison of Fermi Chopper components, using McStas and
contributed components, as well as rotating collimator approximations. It
shows that all implementations are equivalent. However, approximating rotating
guide are 30% faster than McStas Fermi chopper.

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
Fermi 1 Choice of Fermi chopper component to test, with 1=FermiChopper, 3=FermiChopper_ILL, 4=rotating Guide_gravity, 5=rotating Guide_channeled 1
lambda 3.39
width_FC m total slit pack width 0.044
height_FC m height of FC slit pack 0.064
length_FC m length of FC slit pack 0.012
FC_Hz Hz rotation speed. Omega=2*PI*nu in rad/s, nu*60 in rpm 100
Nslit_FC 120
d_SF m distance from Source to FC center 3
d_FD m distance from FC center to Detector 3
phase deg FC phase. Use -0 for automatic 271.92
time_to_arrival 0
time_window_width 0


[ Identification | Description | Input parameters | Output parameters | Links ]

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:21 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:21 CET
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