[ Identification | Description | Input parameters | Links ]

The Mirror_validation Instrument

Comparison of Mirror component and Union version

Identification

• Site: ESS
• Author: Mads Bertelsen (mads.bertelsen@ess.eu)
• Origin: ESS
• Date: October 2025

Description

Comparison of Mirror component and a similar system made with Union components
though with a key difference that a substrate is simulated which results in two
effects: At large angles where no reflection occur, there will be some intensity
from the scattering in the substrate. At very small angles, the reflectivity can
exceed the R0 of the mirror coating, as the ray can be reflected by the Ni
substrate. NCrystal is used to simulate the Ni substrate.
The instrument includes a detector that ignores scattered rays, which should
produce identical results for large angles, though there can still be a tiny
discrepancy at small angles especially if R0 of the mirror coating is lowered.

Example: mcrun Mirror_validation.instr angle=0.7

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
angle	deg	Rotation of sample	0.4
ref_component	1	0 to use Union components, 1 for reference Mirror component	0
R0_value	1	Low-angle reflectivity	0.99
m_value	1	m-value of material	3
Qc_value	AA-1	Critical scattering vector	0.0219
alpha_value	AA	Slope of reflectivity	6.07
W_value	AA-1	Width of supermirror cut-off	0.003

Links

• Source code for Mirror_validation.instr.
• A reference/HTML link for more information

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[ Identification | Description | Input parameters | Links ]

Generated for mcstas 3.6.1

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Last Modified: Friday, 12-Dec-2025 12:58:05 CET