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[ Identification | Description | Input parameters | Links ]
The Monochromator_bent Component
A bent crystal monochromator. Mosacity and bending radius can be set.
Identification
- Site:
- Author: Daniel Lomholt Christensen
- Origin: ILL / Niels Bohr Institute, University of Copenhagen.
- Date: 24 August 2023
Description
This monochromator is an array of crystals, that can be bent. The crystals are placed by the user in the x,y,z pos and rot parameters. The crystal is bent, so that it follows a curve on a cylinder of radius_x. The monochromator lies along the z plane, so when a diffraction angle of theta is desired, it should just be inserted in the ROTATED parameter around the y-axis. Instruments that showcase the use of this component is the "Test_monochromator_bent.instr", and the "ILL_SALSA.instr" under the examples folder. SALSA showcases its complex use in a real instrument, while Test_monochromator_bent makes a simple show of its capabilities.
Input parameters
Parameters in boldface are required; the others are optional.| Name | Unit | Description | Default | |
| zwidth | m | Width of each crystal without bending. | 0.2 | |
| yheight | m | Height of each crystal without bending. | 0.1 | |
| xthickness | m | Thickness of each crystal without bending. | 0.0005 | |
| radius_x | m | Radius of the circle the monochromator bends on in the plane. | 2 | |
| plane_of_reflection | str | The plane of reflection from the material, e.g. "Si400". The list of possible reflections can can be seen in the source code. | "Si400" | |
| angle_to_cut_horizontal | deg | Angle between cut and normal of crystal slab, horizontally | 0 | |
| angle_to_cut_vertical | deg | Angle between cut and normal of crystal slab, vertically ! NOTE: This may not work as intended. | 0 | |
| mosaicity | arcmin | Gaussian mosaicity of the crystal. Always the horizontal mosaicity | 30 | |
| n_crystals | 1 | Number of mono crystals | 1 | |
| mosaic_anisotropy | 1 | Anisotropy of the mosaicity, changes vertical mosaicity to be mosaic_anisotropy*mosaicity | 1 | |
| domainthickness | 1e-6m | Thickness of the crystal domains. | 10 | |
| temperature | K | Temperature of the monochromator in Kelvin. | 300 | |
| optimize | 1 | Flag to tell if the component should optimize for reflections or not. NOTE: May not work perfectly | 1 | |
| x_pos | vector | x-Position of each crystal | NULL | |
| y_pos | vector | y-Position of each crystal | NULL | |
| z_pos | vector | z-Position of each crystal | NULL | |
| x_rot | vector | Rotation around x-axis for each crystal (NOTE: Rotations happen around x, then y, then z.) | NULL | |
| y_rot | vector | Rotation around y-axis for each crystal | NULL | |
| z_rot | vector | Rotation around z-axis for each crystal | NULL | |
| verbose | 1 | Verbosity of the monochromator. Used for debugging. | 0 | |
| draw_as_rectangles | 1 | Flag to visualise component as individual rectangles pr. mono crystal | 0 |
| AT ( | , | , | ) RELATIVE | |||
|---|---|---|---|---|---|---|
| ROTATED ( | , | , | ) RELATIVE |
Links
- Source code for
Monochromator_bent.comp.
[ Identification | Description | Input parameters | Links ]
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