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McStas: Res_sample

[ Identification | Description | Input parameters | Links ]

The Res_sample Component

Sample for resolution function calculation.


  • Site:
  • Author: Kristian Nielsen
  • Origin: Risoe
  • Date: 1999


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.
thicknessmThickness of hollow cylinder in (x,z) plane0
radiusmOuter radius of hollow cylinder0.01
focus_rmRadius of sphere containing target.0.05
E0meVCenter of scattered energy range14
dEmeVhalf width of scattered energy range2
target_ymposition of target to focus at0
focus_xwmhoriz. dimension of a rectangular area0
focus_yhmvert. dimension of a rectangular area0
focus_awdeghoriz. angular dimension of a rectangular area0
focus_ahdegvert. angular dimension of a rectangular area0
xwidthmhoriz. dimension of sample, as a width0
yheightmvert. dimension of sample, as a height0.05
zdepthmdepth of sample0
target_index1relative index of component to focus at, e.g. next is +10


[ Identification | Description | Input parameters | Links ]

Generated on 2024-01-03 11:47:43

Last Modified: Tuesday, 16-Apr-2024 20:05:22 CEST
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