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McStas: Guide_curved Component

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

The Guide_curved Component

Non-focusing curved neutron guide.


  • Author: Ross Stewart
  • Origin: ILL (France).
  • Date: November 18 2003
  • Version:(Unknown)
  • Modification history:
    • E. Farhi, uniformize parameter names (Jul 2008)


Models a rectangular curved guide tube with entrance centered on the Z axis.
The entrance lies in the X-Y plane.  Draws a true depiction
of the guide, and trajectories.  Guide is not focusing.

Example: Guide_curved(w1=0.1, h1=0.1, l=2.0, R0=0.99, Qc=0.021,
               alpha=6.07, m=2, W=0.003, curvature=2700)

This component does not work with gravitation on. Use component Guide_gravity then.
Systematic error on transmitted flux is found to be about 10%.

WARNING: This is a contributed Component.

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  
l m length of guide  
R0 1 Low-angle reflectivity 0.995
Qc AA-1 Critical scattering vector 0.0218
alpha AA Slope of reflectivity 4.38
m 1 m-value of material. Zero means completely absorbing. 2
W AA-1 Width of supermirror cut-off 0.003
curvature m Radius of curvature of the guide 2700


[ 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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