McStas logo McStas - A neutron ray-trace simulation package ILL; PSI; ESS Niels Bohr Institute DTU Physics NEXMAP


About McStas
 Conditions of use
 Project funding

 Other Downloads (share)

Mailing list

Search web/mailinglist

 Wiki (GitHub)
 McStas manual


Report bugs (GitHub)

Code-repository (GitHub)

McStas: Reflectometer Instrument at Templates

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

The Reflectometer Instrument

Horizontal reflectometer, multi-angle of incidence


  • Site: Templates
  • Author: Anette Vickery, contact:
  • Origin: KU
  • Date: November 2011
  • Version:(Unknown)


A horizontal reflectometer. The instrument is built of a 2.5 m long mirror and an inclined elliptical guide. The grazing angle is defined by a set of
slits. The sample size is 4cm x 4cm (horizontal sample).
The role of the mirror is to provide an angle of incidence of up to 4 deg and at the same time avoid a direct line of sight to the source.
The reflectivity is the ratio between the direct beam reflected beam intensities. Therefore two simulations are needed to get the reflectivity curve:

Example: mcrun Reflectometer.instr -n1e10 directbeam=1,thetasample=0.4,Qmin=0,Qmax=0.15 -d directbeam
Example: mcrun Reflectometer.instr -n1e10 directbeam=0,thetasample=0.4,Qmin=0,Qmax=0.15 -d reflectedbeam

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
directbeam 1
Lam_min AA Minimum wavelength emitted by the cold moderator 2.0
Lam_max AA Maximum wavelength emitted by the cold moderator 10
deltatheta % The angular resolution 2
theta_sample deg The grazing angle 1
defineAngle 1
Qmin AA^-1 The minimum value of the interesting Qrange 0
Qmax AA^-1 The maximum value of the interesting Qrange 0.5
straight 1
width m The width of the guide in the case of straight guide walls 0.05


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:21 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:21 CET
Search website mailinglist archive GitHub repos