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McStas: Mirror

[ Identification | Description | Input parameters | Links ]

The Mirror Component

Single mirror plate.


  • Site:
  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: August 1998


Single mirror plate (used to build guides in compound components).
The component Mirror models a single rectangular neutron mirror plate.
It can be used as a sample component or to e.g. assemble a complete neutron
guide by putting multiple mirror components at appropriate locations and
orientations in the instrument definition, much like a real guide is build
from individual mirrors.
Additionally, it may be centered in order to be used as a sample or
monochromator plate, else it starts from AT position.
Reflectivity is either defined by an analytical model (see Component Manual)
or from a two-columns file with q [Angs-1] as first and R [0-1] as second.
In the local coordinate system, the mirror lies in the first quadrant of the
x-y plane, with one corner at (0, 0, 0). Plane is thus perpendicular to the
incoming beam, and should usually be rotated.

Example: Mirror(xwidth=.1, yheight=.1,R0=0.99,Qc=0.021,alpha=6.1,m=2,W=0.003)

Input parameters

Parameters in boldface are required; the others are optional.
reflectstrName of reflectivity file. Format q(Angs-1) R(0-1)0
xwidthmwidth of mirror plate
yheightmheight of mirror plate
R01Low-angle reflectivity0.99
QcAA-1Critical scattering vector0.021
alphaAASlope of reflectivity6.07
m1m-value of material. Zero means completely absorbing.2
WAA-1Width of supermirror cut-off0.003
center1if true (1), the Mirror is centered arount AT position.0
transmit1When true, non reflected neutrons are transmitted through the mirror, instead of being absorbed.0


[ Identification | Description | Input parameters | Links ]

Generated on 2024-01-03 11:47:43

Last Modified: Wednesday, 03-Jan-2024 19:59:11 CET
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