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McStas: Collimator_linear Component

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

The Collimator_linear Component

A simple analytical Soller collimator (with triangular transmission).


  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: August 1998
  • Version:(Unknown)
  • Modification history:
    • GA, June 1999, added transmission


Soller collimator with rectangular opening and specified length. The
transmission function is an average and does not utilize knowledge of the
actual neutron trajectory. A zero divergence disables collimation (then the
component works as a double slit).

Example: Collimator_linear(xmin=-0.1, xmax=0.1, ymin=-0.1, ymax=0.1, length=0.25, divergence=40,transmission=0.7)

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
xmin m Lower x bound on slits -0.02
xmax m Upper x bound on slits 0.02
ymin m Lower y bound on slits -0.05
ymax m Upper y bound on slits 0.05
xwidth m Width of slits 0
yheight m Height of slits 0
length m Distance between input and output slits 0.3
divergence calculated as atan(d/length), where d is the blade spacing [minutes of arc] Divergence horizontal angle 40
transmission 0<=t<=1 [1] Transmission of Soller 1
divergenceV minutes of arc Divergence vertical angle 0

Output parameters

Name Unit Description Default


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:31 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:31 CET
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