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McStas: ISIS_moderator Component

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

The ISIS_moderator Component

ISIS Moderators


  • Author: S. Ansell and D. Champion
  • Origin: ISIS
  • Date: AUGUST 2005
  • Version:(Unknown)


Produces a TS1 or TS2 ISIS moderator distribution.  The Face argument determines which moderator
is to be sampled. Each face uses a different Etable file (the location of which is determined by
the MCTABLES environment variable).  Neutrons are created having a range of energies
determined by the Emin and Emax arguments.  Trajectories are produced such that they pass
through the moderator face (defined by modXsixe and yheight) and a focusing rectangle
(defined by xh,focus_yh and dist).  Please download the documentation for precise instructions for use.

Example:   ISIS_moderator(Face ="water", Emin = 49.0,Emax = 51.0, dist = 1.0, focus_xw = 0.01,
   focus_yh = 0.01, xwidth = 0.074, yheight = 0.074, CAngle = 0.0,SAC= 1)

WARNING: This is a contributed Component.

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
Face word Name of the face - TS2=groove,hydrogen,narrow,broad - - TS1=Water,ch4,h2,merlin or instrument name eg maps, crisp etc. - TS2= W1-9 Emax-9 "hydrogen"
Emin meV Lower edge of energy distribution 49.0
Emax meV Upper edge of energy distribution 51.0
dist m Distance from source to the focusing rectangle 1.0
focus_xw m Width of focusing rectangle 0.01
focus_yh m Height of focusing rectangle 0.01
xwidth m Moderator vertical size 0.074
yheight m Moderator Horizontal size 0.074
CAngle radians Angle from the centre line 0.0
SAC 1/0 [boolean] Apply solid angle correction or not 1
Lmin meV Lower edge of wavelength distribution 0
Lmax meV Upper edge of wavelength distribution 0
target_index 1 relative index of component to focus at, e.g. next is +1 this is used to compute 'dist' automatically. +1
verbose boolean Echo status information at everu 1e5'th neutron 0


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:20 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:20 CET
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