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McStas: Res_sample Component

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

The Res_sample Component

Sample for resolution function calculation.


  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: 1999
  • Version:(Unknown)
  • Modification history:
    • T. Weber, Nov 2020: updated for McStas 3 / OpenACC


An inelastic sample with completely uniform scattering in both Q and
energy. This sample is used together with the Res_monitor component and
(optionally) the mcresplot front-end to compute the resolution function of
triple-axis or inverse-geometry time-of-flight instruments.

The shape of the sample is either a hollow cylinder or a rectangular box. The
hollow cylinder shape is specified with an inner and outer radius.
The box is specified with dimensions xwidth, yheight, zdepth.

The scattered neutrons will have directions towards a given disk and
energies betweed E0-dE and E0+dE.
This target area may also be rectangular if specified focus_xw and focus_yh
or focus_aw and focus_ah, respectively in meters and degrees.
The target itself is either situated according to given coordinates (x,y,z), or
setting the relative target_index of the component to focus at (next is +1).
This target position will be set to its AT position. When targeting to centered
components, such as spheres or cylinders, define an Arm component where to focus at.

Example: Res_sample(thickness=0.001,radius=0.02,yheight=0.4,focus_r=0.05, E0=14.6,dE=2, target_x=0, target_y=0, target_z=1)

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
thickness m Thickness of hollow cylinder in (x,z) plane 0
radius m Outer radius of hollow cylinder 0.01
focus_r m Radius of sphere containing target. 0.05
E0 meV Center of scattered energy range 14
dE meV half width of scattered energy range 2
target_x 0
target_y m position of target to focus at 0
target_z .5
focus_xw m horiz. dimension of a rectangular area 0
focus_yh m vert. dimension of a rectangular area 0
focus_aw deg horiz. angular dimension of a rectangular area 0
focus_ah deg vert. angular dimension of a rectangular area 0
xwidth m horiz. dimension of sample, as a width 0
yheight m vert. dimension of sample, as a height 0.05
zdepth m depth of sample 0
target_index 1 relative index of component to focus at, e.g. next is +1 0


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

Generated automatically by McDoc, Peter Willendrup <> / Wed Jan 12 15:13:20 2022

Last Modified: Wednesday, 12-Jan-2022 16:13:20 CET
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