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McStas: Monochromator_flat

[ Identification | Description | Input parameters | Links ]

The Monochromator_flat Component

Flat Monochromator crystal with anisotropic mosaic.


  • Site:
  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: 1999


Flat, infinitely thin mosaic crystal, useful as a monochromator or analyzer.
For an unrotated monochromator component, the crystal surface lies in the Y-Z
plane (ie. parallel to the beam).
The mosaic is anisotropic gaussian, with different FWHMs in the Y and Z
directions. The scattering vector is perpendicular to the surface.

Example: Monochromator_flat(zmin=-0.1, zmax=0.1, ymin=-0.1, ymax=0.1, mosaich=30.0, mosaicv=30.0, r0=0.7, Q=1.8734)

Monochromator lattice parameter
PG       002 DM=3.355 AA (Highly Oriented Pyrolythic Graphite)
PG       004 DM=1.677 AA
Heusler  111 DM=3.362 AA (Cu2MnAl)
CoFe         DM=1.771 AA (Co0.92Fe0.08)
Ge       111 DM=3.266 AA
Ge       311 DM=1.714 AA
Ge       511 DM=1.089 AA
Ge       533 DM=0.863 AA
Si       111 DM=3.135 AA
Cu       111 DM=2.087 AA
Cu       002 DM=1.807 AA
Cu       220 DM=1.278 AA
Cu       111 DM=2.095 AA

Input parameters

Parameters in boldface are required; the others are optional.
zminmLower horizontal (z) bound of crystal-0.05
zmaxmUpper horizontal (z) bound of crystal0.05
yminmLower vertical (y) bound of crystal-0.05
ymaxmUpper vertical (y) bound of crystal0.05
zwidthmWidth of crystal, instead of zmin and zmax0
yheightmHeight of crystal, instead of ymin and ymax0
mosaicharc minutesHorizontal mosaic (in z direction) (FWHM)30.0
mosaicvarc minutesVertical mosaic (in y direction) (FWHM)30.0
r01Maximum reflectivity0.7
Q1/angstromMagnitude of scattering vector1.8734
DMAAmonochromator d-spacing, instead of Q = 2*pi/DM0


[ Identification | Description | Input parameters | Links ]

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

Last Modified: Tuesday, 16-Apr-2024 20:05:20 CEST
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