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The Template_process McStas Component

12.26  The Template_process McStas Component

A template process for building Union processes

Identification

  • Author: Mads Bertelsen

  • Origin: University of Copenhagen

  • Date: 20.08.15

Description

This is a template for a new contributor to create their own physical process. The comments in this file are meant to teach the user about creating their own process file, rather than explaining this one. For comments on how this code works, look in the Incoherent_process.comp.

Part of the Union components, a set of components that work together and thus sperates geometry and physics within McStas. The use of this component requires other components to be used.

1) One specifies a number of processes using process components like this one 2) These are gathered into material definitions using Union_make_material 3) Geometries are placed using Union_box / Union_cylinder, assigned a material 4) A Union_master component placed after all of the above

Only in step 4 will any simulation happen, and per default all geometries defined before the master, but after the previous will be simulated here.

There is a dedicated manual available for the Union_components

Algorithm: Described elsewhere

Input parameters

Parameters in boldface are required; the others are optional.

Name

Unit

Description

Default

sigma

barns

Incoherent scattering cross section

5.08

packing_factor

1

How dense is the material compared to optimal 0-1

1

unit_cell_volume

Å\(^{3}\)

Unit_cell_volume

13.8

interact_fraction

1

How large a part of the scattering events should use this process 0-1 (sum of all processes in material = 1)

-1

init

string

Deprecated and unused. Accepted so that instruments written for McStas/McXtrace 3.8.7 and earlier, which name the Union_init component here, still compile.

""

Links

  • Component source code found in file Template_process.comp.


Last Modified: Tuesday, 06-Oct-2026 21:19:10 CEST
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