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

The Guide_honeycomb Component

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

Identification

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; k,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, k=1, d=0.0005)

Example values: m=4 Qc=0.02 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  
w2 m Width at the guide exit  
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. 1.0
W AA-1 Width of supermirror cut-off 0.003
k 1 Number of horizontal channels in the guide (>= 1) [1] (k-1 vertical dividing walls) 1
d m Thicxkness 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 -9.81

Output parameters

Name Unit Description Default
GVars 1 internal variables N_reflection[0] total nb of reflections N_reflection[1,2,3,4.5.6] reflections N_reflection[7] total nb neutrons exiting guide N_reflection[8] total nb neutrons entering guide  

Links


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

Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Feb 28 2006