The `Guide_tapering` Component

Models a rectangular tapered guide (many shapes)

Identification

Author: Uwe Filges
Origin: PSI
Date: 22/10/2003
Version: 1.10
Modification history:
- Rob Dalgliesh, ISIS, 2007

Description

Models a rectangular guide tube centered on the Z axis. The entrance lies
in the X-Y plane.
The guide may be tapered.

The component includes a feature to read in self-defined functions for
guide tapering. Under the parameter 'option' the KEYWORD 'file=' offers
the possibility to read in parameters from an ASC-file. The file structure
is shown below in the example. It is important to know that the first
3 lines will be interpreted as comments.
Afterwards the dimension of each guide segment must be defined. The
length of each segment is constant l(i)=l/segments . The number of
segments is defined through the number of lines minus the first 3
lines taken from the Input-File.

Example Input-File:

c Guide_tapering.comp
c i = 0 - 199 segments
c h1(i)     h2(i)   w1(i)    w2(i)
0.120000 0.119850 0.020000 0.020000
0.119850 0.119700 0.020000 0.020000
0.119700 0.119550 0.020000 0.020000
0.119550 0.119400 0.020000 0.020000
0.119400 0.119250 0.020000 0.020000
0.119250 0.119100 0.020000 0.020000
...

 Example1:Guide_tapering(w1=0.1, h1=0.18, linw=0.1, loutw=0.1,
 linh=0.1, louth=0.1, l=1.5, option="elliptical", R0=0.99,
 Qcx=0.021, Qcy=0.021, alphax=6.07, alphay=6.07, W=0.003,
 mx=1, my=1, segno=800)

 Example2:Guide_tapering(w1=0, h1=0, linw=0, loutw=0,
 linh=0, louth=0, l=1.5, option="file=ownfunction.txt", R0=0.99,
 Qcx=0.021, Qcy=0.021, alphax=6.07, alphay=6.07, W=0.003,
 mx=1, my=1)

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

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
option	str	define the input function for the curve of the guide walls options are: "elliptical" - define elliptical function of guide walls "parabolical" - define parabolical function of guide walls "file=[filename]" - read in ASC-file with arbitrary definition for the curve of the guide walls	0
segno	1	number of segments (z-axis) for cutting the tube	800
w1	m	Width at the guide entry	0
h1	m	Height at the guide entry	0
l	m	length of guide
linw	m	distance of 1. focal point and real guide entry - left and right horizontal mirrors	0
loutw	m	distance of real guide exit and 2nd focal point - left and right horizontal mirrors	0
linh	m	distance of 1st focal point and real guide entry - top and bottom vertical mirrors	0
louth	m	distance of real guide exit and 2nd focal point - top and bottom vertical mirrors	0
R0	1	Low-angle reflectivity	0.99
Qcx	AA-1	Critical scattering vector for left and right vertical mirrors in each channel	0.021
Qcy	AA-1	Critical scattering vector for top and bottom mirrors	0.021
alphax	AA	Slope of reflectivity for left and right vertical mirrors in each channel	6.07
alphay	AA	Slope of reflectivity for top and bottom mirrors	6.07
W	AA-1	Width of supermirror cut-off for all mirrors	0.003
mx	1	m-value of material for left and right vertical mirrors in each channel. Zero means completely absorbing.	1
my	1	m-value of material for top and bottom mirrors. Zero means completely absorbing.	1

Output parameters

Name	Unit	Description	Default
w1c
w2c
ww
hh
whalf
hhalf
lwhalf
lhhalf
h1_in
h2_out
w1_in
w2_out
l_seg
seg
h12
h2
w12
w2
a_ell_q
b_ell_q
lbw
lbh
mxi
u1
u2
div1
p2_para
test
Div1
i
ii
seg
fu
pos
file_name
ep
num

The Guide_tapering Component

Identification

Description

Input parameters

Output parameters

Links

The `Guide_tapering` Component