McXtrace - An X-ray ray-trace simulation package

[ Identification | Description | Input parameters | Links ]

The Incoherent_process Component

A sample component to separate geometry and phsysics

Identification

• Site:
• Author: Mads Bertelsen and Erik B Knudsen
• Origin: ESS DMSC & DTU Physics
• Date: 20.08.15

Description

This Union_process is based on the Incoherent.comp component originally written
by Kim Lefmann and Kristian Nielsen

Part of the Union components, a set of components that work together and thus
separates geometry and physics within McXtrace.
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
f_QE	1	Fraction of quasielastic scattering (rest is elastic)	0
gamma	1	Lorentzian width of quasielastic broadening (HWHM)	0
packing_factor	1	How dense is the material compared to optimal 0-1	1
unit_cell_volume			13.8
interact_fraction			-1
init	string	name of Union_init component (typically "init", default)	"init"

AT (	,	,		) RELATIVE		Generate to clipboard
ROTATED (	,	,		) RELATIVE

Links

• Source code for Incoherent_process.comp.
• The test/example instrument Test_Phonon.instr.

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[ Identification | Description | Input parameters | Links ]

Generated on mcxtrace 3.6.14

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Last Modified: Monday, 13-Apr-2026 11:30:06 CEST