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McStas: Monochromator_flat Component

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

The Monochromator_flat Component

Flat Monochromator crystal with anisotropic mosaic.


  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: 1999
  • Version:(Unknown)


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.
Name Unit Description Default
zmin m Lower horizontal (z) bound of crystal -0.05
zmax m Upper horizontal (z) bound of crystal 0.05
ymin m Lower vertical (y) bound of crystal -0.05
ymax m Upper vertical (y) bound of crystal 0.05
zwidth m Width of crystal, instead of zmin and zmax 0
yheight m Height of crystal, instead of ymin and ymax 0
mosaich FWHM [arc minutes] Horizontal mosaic (in z direction) 30.0
mosaicv FWHM [arc minutes] Vertical mosaic (in y direction) 30.0
r0 1 Maximum reflectivity 0.7
Q 1/angstrom Magnitude of scattering vector 1.8734
DM AA monochromator d-spacing, instead of Q = 2*pi/DM 0

Output parameters

Name Unit Description Default


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:31 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:31 CET
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