[ Identification | Description | Input parameters | Output parameters | Links ]
Monochromator_curved
ComponentDouble bent infinitely thin mosaic crystal, useful as a monochromator or analyzer. which uses a small-mosaicity approximation and taking into account higher order scattering. The mosaic is anisotropic gaussian, with different FWHMs in the Y and Z directions. The scattering vector is perpendicular to the surface. For an unrotated monochromator component, the crystal plane lies in the y-z plane (ie. parallel to the beam). The component works in reflection, but also transmits the non-diffracted beam. Reflectivity and transmission files may be used. The slabs are positioned in the vertical plane (not on a cylinder/sphere), and are rotated according to the curvature radius. When curvatures are set to 0, the monochromator is flat. The curvatures approximation for parallel beam focusing to distance L, with monochromator rotation angle A1 are: RV = 2*L*sin(DEG2RAD*A1); RH = 2*L/sin(DEG2RAD*A1); When you rotate the component by A1 = asin(Q/2/Ki)*RAD2DEG, do not forget to rotate the following components by A2=2*A1 (for 1st order) ! Example: Monochromator_curved(zwidth=0.01, yheight=0.01, gap=0.0005, NH=11, NV=11, mosaich=30.0, mosaicv=30.0, r0=0.7, Q=1.8734) Example values for lattice parameters PG 002 DM=3.355 AA (Highly Oriented Pyrolytic Graphite) PG 004 DM=1.607 AA Heusler 111 DM=3.362 AA (Cu2MnAl) CoFe DM=1.771 AA (Co0.92Fe0.08) Ge 311 DM=1.714 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
Name | Unit | Description | Default |
---|---|---|---|
reflect | str | reflectivity file name of text file as 2 columns [k, R] | 0 |
transmit | str | transmission file name of text file as 2 columns [k, T] | 0 |
zwidth | m | horizontal width of an individual slab | 0.01 |
yheight | m | vertical height of an individual slab | 0.01 |
gap | m | typical gap between adjacent slabs | 0.0005 |
NH | columns | number of slabs horizontal | 11 |
NV | rows | number of slabs vertical | 11 |
mosaich | arc minutes | Horisontal mosaic FWHM | 30.0 |
mosaicv | arc minutes | Vertical mosaic FWHM | 30.0 |
r0 | 1 | Maximum reflectivity. O unactivates component | 0.7 |
t0 | 0.3 | ||
Q | AA-1 | Scattering vector | 1.8734 |
RV | m | radius of vertical focussing. flat for 0 | 0 |
RH | m | radius of horizontal focussing. flat for 0 | 0 |
DM | Angstrom | monochromator d-spacing instead of Q=2*pi/DM | 0 |
mosaic | arc minutes | sets mosaich=mosaicv | 0 |
width | m | total width of monochromator | 0 |
height | m | total height of monochromator | 0 |
verbose | 0/1 | verbosity level | 0 |
Name | Unit | Description | Default |
---|---|---|---|
mos_rms_y | |||
mos_rms_z | |||
mos_rms_max | |||
mono_Q | |||
SlabWidth | |||
SlabHeight | |||
rTable | |||
tTable | |||
row | 1:NV | row index for last hit blade | |
col | 1:NH | column index for last hit blade |
Monochromator_curved.comp
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[ Identification | Description | Input parameters | Output parameters | Links ]
Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Fri Mar 12 17:53:42 2010