The `Pol_mirror` Component

Polarising mirror.

Identification

Author: Peter Christiansen
Origin: RISOE
Date: July 2006
Version: 1.4

Description

This component models a rectangular infinitely thin mirror.
For an unrotated component, the mirror surface lies in the Y-Z
plane (ie. parallel to the beam).
It relies on similar physics as the Monochromator_pol.
The reflec function (see e.g. share/ref-lib for examples) 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)
For now we assume:
P(Transmit|Q) = 1 - P(Reflect|Q)
i.e. NO ABSORPTION!

There are 3 options:
1) Reflect and transmit (randomly choose) [default]
2) Only reflect (reduce weight)
3) Only transmit (reduce weight)

The parameters can either be 
double pointer initializations (e.g. {1.0, 0.0219, 6.07, 2.0, 0.003}) 
or table names (e.g."supermirror_m2.rfl" AND useTables=1).
NB! This might cause warnings by the compiler that can be ignored.

Examples:
Reflection function parametrization 
Pol_mirror(zw = 0.40, yh = 0.40, option=1,
	     rUpFunc=StdReflecFunc, rUpPar={1.0, 0.0219, 6.07, 2.0, 0.003})

Table function 
Pol_mirror(zw = 0.40, yh = 0.40, option=2, 
	     rUpFunc=TableReflecFunc, rUpPar="supermirror_m2.rfl",
	     rDownFunc=TableReflecFunc, rDownPar="supermirror_m3.rfl", 
	     useTables=1)

See also the example instrument Test_Pol_Mirror (under tests).  

GRAVITY: YES
POLARISATION: YES

%BUGS 
NO ABSORPTION

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
rUpFunc	1	Reflection function for spin up (q, par, r)	StdReflecFunc
rDownFunc	1	Reflection function for spin down (q, par, r)	rUpFunc
rUpPar	1	Parameters for rUpFunc	{0.99
rDownPar	1	Parameters for rDownFunc	rUpPar
useTables	1	Parameters are 0: Values, 1: Table names	0
zw	m	Width of the mirror
yh	m	Height of the mirror
option	1	1:Reflect/trasmit, 2:Reflect only, 3:Transmit only	1

Output parameters

Name	Unit	Description	Default
rUpParPtr
rDownParPtr

The Pol_mirror Component

Identification

Description

Input parameters

Output parameters

Links

The `Pol_mirror` Component