Dear Fluka forum,
I trying to get to grips with using Fluka for simulations of gamma-ray generation from a Na22 source.
I have started with a toy model where I want to track the energy deposition and spectrum of gamma-rays emitted from a small cylindrical Na22 sample placed in a sphere of water. I believe I have set the source up correctly using:
BEAM 0 10000.0 ISOTOPE
HI-PROPE 11 22
RADDECAY 2 0
BEAMPOS 0 0 0 0 0
BEAMPOS 0 0.1 0 0.2 CYLI-VOL
To track the energy deposition I used USRBIN:
USRBIN 10 PHOTON -21 20 20 20DoseEqGrid
USRBIN -20 -20 -20 500 500 500 &
and for the spectrum USRBDX:
USRBDX -1 PHOTON -22 WAT VOID EnSpec
USRBDX 100E-7 1E-7 3000 1 &
However, currently written by the USRBIN or USRBDX routines which means flair fails to plot the results.
I can see a proportion of secondary photons are being created but am unsure why I can’t see then in USRBIN/USRBDX:
Number of secondaries generated in inelastic interactions per beam particle:
Prompt radiation Radioactive decays
....
0.0000E+00 ( 0.0%) 1.0004E+00 (34.5%) PHOTON
In addition when trying to plot the USRBIN the log shows this in the output - could this warning be part of the problem - I am unsure how to start troubleshooting the particle weight being reset.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!! Something weird occurred: the total !!!!
!!!! particle weight is reset to 1. Please !!!!
!!!! check carefully the input and the !!!!
!!!! results !!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I attached the .flair file here.
gamma_product.flair (1.7 KB)