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McStas: Guide_simple Component

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

The Guide_simple Component

Neutron guide.


  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: September 2 1998
  • Version:(Unknown)


Models a rectangular guide tube centered on the Z axis. The entrance lies
in the X-Y plane.
For details on the geometry calculation see the description in the McStas
reference manual.
The reflectivity profile may either use an analytical mode (see Component
Manual) or a 2-columns reflectivity free text file with format
[q(Angs-1) R(0-1)].

Example: Guide(w1=0.1, h1=0.1, w2=0.1, h2=0.1, l=2.0, R0=0.99, Qc=0.021, alpha=6.07, m=2, W=0.003

May 2005: extensive internal test, no bugs found
Validated by: K. Lieutenant

This component does not work with gravitation on. Use component Guide_gravity then.

Example values: m=4 Qc=0.0219 W=1/300 alpha=6.49 R0=1

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
w1 m Width at the guide entry  
h1 m Height at the guide entry  
w2 m Width at the guide exit 0
h2 m Height at the guide exit 0
l m length of guide  
R0 1 Low-angle reflectivity 0.99
Qc AA-1 Critical scattering vector 0.0219
alpha AA Slope of reflectivity 6.07
m 1 m-value of material. Zero means completely absorbing. glass/SiO2 Si Ni Ni58 supermirror Be Diamond m= 0.65 0.47 1 1.18 2-6 1.01 1.12 2
W AA-1 Width of supermirror cut-off 0.003


[ 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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