Neutron guide initiated using Virtual_mcnp_ss_input.comp, and replacing Virtual_mcnp_ss_output.comp - see examples//Test_SSR_SSW_Guide.instr
Author: Esben klinkby and Peter Willendrup
Date: Marts 2012
Based on Kristian Nielsens Guide.comp
Models a rectangular guide tube centered on the Z axis. The entrance lies
in the X-Y plane.
The component must be initiated after Virtual_mcnp_ss_input.comp,
and replaces Virtual_mcnp_ss_output.comp - see examples/Test_SSR_SSW_Guide.instr.
The basic idea is, that rather than discarding unreflected (i.e. absorbed)
neutrons at the guide mirrors, these neutron states are stored on disk.
Thus, after the McStas simulation a MCNP simulation can be performed based
on the un-reflected neutrons - intended for shielding studies.
(details: we don't deal with actual neutrons, so what is transferred between
simulations suites is neutron state parameters: pos,mom,time,weight. The latter is
whatever remains after reflection.
For details on the geometry calculation see the description in the McStas
The reflectivity profile may either use an analytical mode (see Component
Manual) or a 2-columns reflectivity free text file with format
Example: Virtual_mcnp_ss_Guide(w1=0.1, h1=0.1, w2=0.1, h2=0.1, l=2.0,
R0=0.99, Qc=0.021, alpha=6.07, m=2, W=0.003
Upcomming in 2012 based on ESS shielding
Validated by: D. Ene & E. Klinkby
This component does not work with gravitation on. Use component Guide_gravity then
(doesn't work with SSR/SSW unfortunately)
Example values: m=4 Qc=0.0219 W=1/300 alpha=6.49 R0=1
Parameters in boldface are required;
the others are optional.
Reflectivity file name. Format
Width at the guide entry
Height at the guide entry
Width at the guide exit
Height at the guide exit
length of guide
Critical scattering vector
Slope of reflectivity
m-value of material. Zero means completely absorbing.