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McStas: Test_Mirror_FlatEllipse

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

The Test_Mirror_FlatEllipse Instrument

Compares a (nearly flat) FlatEllipse_finite_mirror with Mirror.comp

Identification

  • Site: Tests_optics
  • Author: Peter Willendrup
  • Origin: DTU
  • Date: October 2026

Description

A collimated, polychromatic beam hits a single mirror at grazing angle theta.
The mirror is either Mirror.comp with transmit=1, or a single-mirror
FlatEllipse_finite_mirror (conic.h, mirror_width=0) with foci at +/- focus,
which for the default focus=10 km is flat to within ~1e-10 rad over the mirror.
Reflected and transmitted beams are recorded separately as function of wavelength,
and the two COMP settings should give the same result.

COMP=0: Mirror, transmit=1
COMP=1: FlatEllipse_finite_mirror, nummirror=1, mirror_width=0

Examples

(Test cases in bold)
  • Test: COMP=0 Detector: L_refl_I=8.98208e-07
  • Test: COMP=1 Detector: L_refl_I=8.98208e-07
  • Test: COMP=0 Detector: L_trans_I=7.01789e-07
  • Test: COMP=1 Detector: L_trans_I=7.01789e-07

Input parameters

Parameters in boldface are required; the others are optional.
NameUnitDescriptionDefault
COMP1Mirror implementation, see description0
thetadegGrazing angle of the beam on the mirror1
lengthmMirror length1
m1Mirror m-value2
R01Low-angle reflectivity0.99
QcAA^-1Critical scattering vector0.0217
alphaAASlope of reflectivity6.07
WAA^-1Width of supermirror cut-off0.003
LminAAMinimum source wavelength1
LmaxAAMaximum source wavelength11
focusmDistance from the mirror centre to each of the ellipse foci1e4
r0mDistance from the FlatEllipse_finite_mirror optical axis to the mirror0.1

Links


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

Generated for mcstas 3.10.0


Last Modified: Friday, 23-Oct-2026 18:32:10 CEST
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