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McStas: AF_HB_1D_process

[ Identification | Description | Input parameters | Links ]

The AF_HB_1D_process Component

1D Antiferromagnetic Heisenberg chain


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


1D Antiferromagnetic Heisenberg chain

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.
atom_distanceAADistance between atom's in chain1
number_density1/AA^3Number of scatteres per volume0
unit_cell_volumeAA^3Unit cell volume (set either unit_cell_volume or number density)0
A_constantunitlessConstant from Müller paper 1981, probably somewhere between 1 and 1.51
J_interactionmeVExchange constant1
packing_factor1How dense is the material compared to optimal 0-11
interact_fraction1How large a part of the scattering events should use this process 0-1 (sum of all processes in material = 1)-1
initstringname of Union_init component (typically "init", default)"init"


[ Identification | Description | Input parameters | Links ]

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

Last Modified: Wednesday, 03-Jan-2024 19:59:10 CET
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