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McStas: Guide_four_side

[ Identification | Description | Input parameters | Links ]

The Guide_four_side Component

Guide with four side walls

Identification

  • Site:
  • Author: Tobias Panzner
  • Origin: PSI
  • Date: 07/08/2010

Description

This component models a guide with four side walls.
As user you can controll the properties of every wall separatly. All togther you have up to
8 walls: 4 inner walls and 4 outer walls.

Every single wall can have a elliptic, parabolic or straight shape.
All four sides of the guide are independent from each other.
In the elliptic case the side wall shape follows the equation x^2/b^2+(z+z0)^2/a^2=1
(the center of the ellipse is located at (0,-z0)).
In the parabolic case the side wall shape follows the equation z=b-ax^2;mc
In the straight case the side wall shape follows the equation z=l/(w2-w1)*x-w1.

The shape selection is done by the focal points. The focal points are located at the
z-axis and are defined by their distance to the entrance or exit window of the guide
(in the following called 'focal length').

If both focal lengths for one wall are zero it will be a straight wall (entrance and
exit width have to be given in the beginning).

If one of the focal lengths is not zero the shape will be parabolic (only the entrance width
given in the beginning is recognized; exit width will be calculated). If the the entrance
focal length is zero the guide will be a focusing devise.
If the exit focal length is zero it will be defocusing devise.

If both focals are non zero the shape of the wall will be elliptic (only the entrance width
given in the beginning is recognized; exit width will be calculated).

Notice: 1.)The focal points are in general located outside the guide (positive focal lengths).
Focal points inside the guide need to have negative focal lengths.
2.)The exit width parameters (w2r, w2l, h2u,h2d) are only taken into account if the
walls have a linear shape. In the ellitic or parabolic case they will be ignored.

For the inner channel: the outer side of each wall is calculated by the component in depentence
of the wallthickness and the shape of the inner side.

Each of walls can have a own indepenting reflecting layer (defined by an input file)
or it can be a absorber or it can be transparent.

The reflectivity properties can be given by an input file (Format [q(Angs-1) R(0-1)]) or by
parameters (Qc, alpha, m, W).

%BUGS
This component does not work with gravitation on.

This component does not work correctly in GROUP-modus.

Input parameters

Parameters in boldface are required; the others are optional.
NameUnitDescriptionDefault
RIreflect(str) Name of relfectivity file for the right inner wall.0
LIreflect(str) Name of relfectivity file for the left inner wall.0
UIreflect(str) Name of relfectivity file for the top inner wall.0
DIreflect(str) Name of relfectivity file for the bottom inner wall.0
ROreflect(str) Name of relfectivity file for the right outer wall.0
LOreflect(str) Name of relfectivity file for the left outer wall.0
UOreflect(str) Name of relfectivity file for the top outer wall.0
DOreflect(str) Name of relfectivity file for the bottom outer wall.0
w1lmWidth at the left guide entry (positive x-axis)0.002
w2lmWidth at the left guide exit (positive x-axis)0.002
linwl0
loutwl0
w1rmWidth at the right guide entry (negative x-axis)0.002
w2rmWidth at the right guide exit (negative x-axis)0.002
linwr0.0
loutwr0
h1umHeight at the top guide entry (positive y-axis)0.002
h2umHeight at the top guide entry (positive y-axis)0.002
linhu0.0
louthu0
h1dmHeight at the bottom guide entry (negative y-axis)0.002
h2dmHeight at the bottom guide entry (negative y-axis)0.002
linhd0.0
louthd0
lmlength of guide (DEFAULT = 0)0
R01Low-angle reflectivity (DEFAULT = 0.99)0.99
QcxlAA-1Critical scattering vector for left vertical0.0217
QcxrAA-1Critical scattering vector for right vertical0.0217
QcyuAA-1Critical scattering vector for top inner wall0.0217
QcydAA-1Critical scattering vector for bottom inner wall0.0217
alphaxlAASlope of reflectivity for left vertical6.07
alphaxrAASlope of reflectivity for right vertical6.07
alphayuAASlope of reflectivity for top inner wall6.07
alphaydAASlope of reflectivity for bottom inner wall6.07
WxrAA-1Width of supermirror cut-off for right inner wall0.003
WxlAA-1Width of supermirror cut-off for left inner wall0.003
WyuAA-1Width of supermirror cut-off for top inner wall0.003
WydAA-1Width of supermirror cut-off for bottom inner wall0.003
mxr1m-value of material for right vertical inner wall.3.6
mxl1m-value of material for left vertical inner wall.3.6
myu1m-value of material for top inner wall3.6
myd1m-value of material for bottom inner wall3.6
QcxrOWAA-1Critical scattering vector for right vertical0.0217
QcxlOWAA-1Critical scattering vector for left vertical0.0217
QcyuOWAA-1Critical scattering vector for top outer wall0.0217
QcydOWAA-1Critical scattering vector for bottom outer wall0.0217
alphaxlOWAASlope of reflectivity for left vertical6.07
alphaxrOWAASlope of reflectivity for right vertical6.07
alphayuOWAASlope of reflectivity for top outer wall6.07
alphaydOWAASlope of reflectivity for bottom outer wall6.07
WxrOWAA-1Width of supermirror cut-off for right outer wall0.003
WxlOWAA-1Width of supermirror cut-off for left outer wall0.003
WyuOWAA-1Width of supermirror cut-off for top outer wall0.003
WydOWAA-1Width of supermirror cut-off for bottom outer wall0.003
mxrOW1m-value of material for right vertical outer wall0
mxlOW1m-value of material for left vertical outer wall0
myuOW1m-value of material for top outer wall0
mydOW1m-value of material for bottom outer wall0
rwallthickmthickness of the right wall (DEFAULT = 0.001 m)0.001
lwallthickmthickness of the left wall (DEFAULT = 0.001 m)0.001
uwallthickmthickness of the top wall (DEFAULT = 0.001 m)0.001
dwallthickmthickness of the bottom wall(DEFAULT = 0.001 m)0.001
AT ( , , ) RELATIVE
ROTATED ( , , ) RELATIVE

Links


[ Identification | Description | Input parameters | Links ]

Generated on 2023-09-19 20:01:36


Last Modified: Tuesday, 17-Sep-2024 05:31:13 CEST
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