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McStas: Powder_process

[ Identification | Description | Input parameters | Links ]

The Powder_process Component

Port of the PowderN process to the Union components


  • Site:
  • Author: Mads Bertelsen
  • Origin: University of Copenhagen
  • Date: 20.08.15


This Union_process is based on the PowderN.comp component originally written
by P. Willendrup, L. Chapon, K. Lefmann, A.B.Abrahamsen, N.B.Christensen,

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
Described elsewhere

Input parameters

Parameters in boldface are required; the others are optional.
reflectionsstringInput file for reflections. No scattering if NULL or "" [string]"NULL"
packing_factor1How dense is the material compared to optimal 0-11
VcAA^3Volume of unit cell=nb atoms per cell/density of atoms.0
delta_d_d0/1Global relative delta_d_d/d broadening when the 'w' column is not available. Use 0 if ideal.0
DW1Global Debye-Waller factor when the 'DW' column is not available. Use 1 if included in F20
nb_atoms1Number of sub-unit per unit cell, that is ratio of sigma for chemical formula to sigma per unit cell1
d_phidegAngle corresponding to the vertical angular range to focus to, e.g. detector height. 0 for no focusing.0
densityg/cm^3Density of material. rho=density/weight/1e24*N_A.0
weightg/molAtomic/molecular weight of material.0
barns1Flag to indicate if |F|^2 from 'reflections' is in barns or fm^2 (barns=1 for laz, barns=0 for lau type files).1
StrainppmGlobal relative delta_d_d/d shift when the 'Strain' column is not available. Use 0 if ideal.0
interact_fraction1How large a part of the scattering events should use this process 0-1 (sum of all processes in material = 1)-1
formatno quotesName of the format, or list of column indexes (see Description).{0, 0, 0, 0, 0, 0, 0, 0, 0}


[ Identification | Description | Input parameters | Links ]

Generated on 2023-09-19 20:01:36

Last Modified: Tuesday, 16-Apr-2024 20:05:21 CEST
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