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McStas: Pol_bender Component

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

The Pol_bender Component

Polarising bender.

Identification

  • Author: Peter Christiansen
  • Origin: RISOE
  • Date: August 2006
  • Version: $Revision$

Description

Based on Guide_curved written by Ross Stewart.
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 with multiple slits (but without spacers), and trajectories.
It relies on similar physics as the Monochromator_pol.
The reflec function and parameters are passed to this component to
give a bigger freedom. 
The up direction is hardcoded to be along the y-axis (0, 1, 0)

The guide is asummed to have half a spacer on each side:
   slit1  slit2  slit3 
 |+     ++     ++     +|
 |+     ++     ++     +|  
 <---------------------> xwidth
 <------> xwidth/nslit (nslit=3)
        <> d

The reflection functions and parameters defaults as follows:
Bot defaults to Top, Left defaults to Top, Right defaults to left.
Down defaults to down and up defaults to up for all functions and 
Top(Up and Down) defaults to StdReflecFunc and {0.99,0.0219,6.07,2.0,0.003}
which stands for {R0, Qc, alpha, m, W}.

Example: 
Pol_bender(xwidth = 0.08, yheight = 0.08, length = 1.0, radius= 10.0, 
	     nslit=5, d=0.0, endFlat=0, drawOption=2,
	     rTopUpPar={0.99, 0.0219, 6.07, 3.0, 0.003},
	     rTopDownPar={0.99, 0.0219, 6.07, 1.0, 0.003})

See also the example instruments Test_Pol_Bender and 
Test_Pol_Bender_Vs_Guide_Curved (under tests).

%BUGS 
This component has been against tested Guide_curved and found to
give the same intensities. Gravity option has not been tested.

GRAVITY: YES (when gravity is along y-axis)

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
rTopUpFunc 1 Top reflection function for spin up (q, *par, *reflecProb) StdReflecFunc
rTopDownFunc 1 Top reflection function for spin down (q, *par, *reflecProb) StdReflecFunc
rBotUpFunc rTopUpFunc
rBotDownFunc rTopDownFunc
rLeftUpFunc rTopUpFunc
rLeftDownFunc rTopDownFunc
rRightUpFunc rLeftUpFunc
rRightDownFunc rLeftDownFunc
rTopUpPar 1 Parameters for rTopUpFunc {0.99
rTopDownPar 1 Parameters for rTopDownFunc {0.99
rBotUpPar rTopUpPar
rBotDownPar rTopDownPar
rLeftUpPar rTopUpPar
rLeftDownPar rTopDownPar
rRightUpPar rLeftUpPar
rRightDownPar rLeftDownPar
xwidth m Width at the guide entry  
yheight m Height at the guide entry  
length m length of guide along center  
radius  
G 9.8
nslit 1 Number of slits 1
d m Width of spacers (subdividing absorbing walls) 0.0
debug 1 if debug > 0 print out some internal parameters 0
endFlat 1 If endflat>0 then entrance and exit planes are parallel. 0
drawOption 1 1: fine(all slits/90 points per arc), 2: normal (max 20/40), 3: rough (max 5/10) 1

Output parameters

Name Unit Description Default
localG m/s/s Gravity vector in guide reference system  
normTopBot  
normIn  
normOut  
pointTop  
pointBot  
pointIn  
pointOut  
rTopUpParPtr  
rTopDownParPtr  
rBotUpParPtr  
rBotDownParPtr  
rLeftUpParPtr  
rLeftDownParPtr  
rRightUpParPtr  
rRightDownParPtr  

Links


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

Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Fri Mar 17 20:40:06 2017


Last Modified: Friday, 17-Mar-2017 21:40:06 CET
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