[ Identification | Description | Input parameters | Links ]

The Guide_honeycomb Component

Neutron guide with gravity and honeycomb geometry. Can be channeled and focusing.

Identification

• Site:
• Author: G. Venturi
• Origin: ILL (France).
• Date: Apr 2003

Description

Models a honeycomb guide tube centered on the Z axis. The entrance lies
in the X-Y plane. Gravitation applies also when reaching the guide input
window. The guide can be channeled (hexagonal channel section; nslit,d parameters).
The guide coating specifications may be entered via different ways (global,
or for each wall m-value).
For details on the geometry calculation see the description in the McStas
reference manual.

Example: Guide_honeycomb(w1=0.1, w2=0.1, l=12,
R0=0.99, Qc=0.0219, alpha=6.07, m=1.0, W=0.003, nslit=1, d=0.0005)

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
w1	m	Width at the guide entry
w2	m	Width at the guide exit. If zero, sets w2=w1.	0
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.	1.0
W	AA-1	Width of supermirror cut-off	0.003
nslit	1	Number of horizontal channels in the guide (>= 1) [1]	1
d	m	Thickness of subdividing walls [0]	0.0005
mleftup	1	m-value of material for leftup. oblique mirror	-1
mrightup	1	m-value of material for rightdown. oblique mirror	-1
mleftdown	1	m-value of material for rightdown. oblique mirror	-1
mrightdown	1	m-value of material for leftup. oblique mirror	-1
mleft	1	m-value of material for left. vertical mirror	-1
mright	1	m-value of material for right. vertical mirror	-1
G	m/s2	Gravitation norm. 0 value disables G effects.	0

AT (	,	,		) RELATIVE		Generate
ROTATED (	,	,		) RELATIVE

Links

• Source code for Guide_honeycomb.comp.

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[ Identification | Description | Input parameters | Links ]

Generated on 2025-05-08 13:31:31

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Last Modified: Monday, 30-Jun-2025 11:05:11 CEST