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McStas: Guide_m Component

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

The Guide_m Component

Neutron guide.

Identification

  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: September 2 1998, Modified 2013
  • Version: 1.32
  • Modification history:
    • Nikolaos Tsapatsaris to accept differently coated mirror planes

Description

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

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

%BUGS
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

WARNING: This is a contributed Component.

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
reflect str Reflectivity file name. Format [q(Angs-1) R(0-1)] 0
w1 m Width at the guide entry  
h1 m Height at the guide entry  
w2 m Width at the guide exit  
h2 m Height at the guide exit  
l m length of guide  
R0_left 1 Low-angle reflectivity, left mirror. 0.99
R0_right 1 Low-angle reflectivity, right mirror. 0.99
R0_top 1 Low-angle reflectivity, top mirror. 0.99
R0_bottom 1 Low-angle reflectivity, bottom mirror. 0.99
Qc_left AA-1 Critical scattering vector, left mirror. 0.0219
Qc_right AA-1 Critical scattering vector, right mirror. 0.0219
Qc_top AA-1 Critical scattering vector, top mirror. 0.0219
Qc_bottom AA-1 Critical scattering vector, bottom mirror. 0.0219
alpha_left AA Slope of reflectivity, left mirror. 6.07
alpha_right AA Slope of reflectivity, right mirror. 6.07
alpha_top AA Slope of reflectivity, top mirror. 6.07
alpha_bottom AA Slope of reflectivity, bottom mirror. 6.07
m_left 1 m-value of material, left mirror. Zero means completely absorbing. 2
m_right 1 m-value of material, right mirror. Zero means completely absorbing. 2
m_top 1 m-value of material, top mirror. Zero means completely absorbing. 2
m_bottom 1 m-value of material, bottom mirror. Zero means completely absorbing. 2
W_left AA-1 Width of supermirror cut-off, left mirror. 0.003
W_right AA-1 Width of supermirror cut-off, right mirror. 0.003
W_top AA-1 Width of supermirror cut-off, top mirror. 0.003
W_bottom AA-1 Width of supermirror cut-off, bottom mirror. 0.003

Output parameters

Name Unit Description Default
pTable  
m  
alpha  
Qc  
R0  
W  

Links


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

Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Fri Sep 23 18:47:27 2022


Last Modified: Friday, 23-Sep-2022 20:47:27 CEST
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