Elastic NEUTRON,inelastic NEUTRON and fission NEUTRON

Dear FLUKA experts,
Hello! I have some questions about the ‘.out’ file for the experts. In the ‘.out’ file there is an entry ‘Number of secondaries created by low energy neutron per beam particle:’ as shown in figure 1 and 2. When I add up all the percentages in the list, I find that the result is greater than 100%, and the excess is exactly the percentage of ‘inelastic NEUTRON’. Why is this? I don’t understand the difference and connection between ‘elastic NEUTRON’, ‘inelastic NEUTRON’ and ‘fission NEUTRON’. In my understanding, inelastic should include fission, but sometimes ‘inelastic NEUTRON’ is greater than ‘fission NEUTRON’ and sometimes ‘fission NEUTRON’ is greater than ‘inelastic NEUTRON’.
I hope the experts can help me. Thank you very much for your help and answer! Looking forward to your reply. Wish you the best of luck in everything.
Very thankful!!!



Lin

Dear @linjunze

thank you for the bug report.
Indeed there was a problem in this statistics table, which did not include the “inelastic NEUTRON” contribution in the final normalization.

  • elastic - total number of low energy neutron elastic collisions (n,el)
  • inelastic - total number of neutrons generated by any inelastic reaction as (n,n’), (n,n*) except fission
  • fission - neutrons generated only from fission reactions
  • PHOTON - almost from all reactions except elastic and some inelastic channels e.g. (n,*) directly to ground level
  • others - all other particles generated by inelastic interactions

The fix will appear with the next FLUKA release scheduled in the coming days.

1 Like

Dear @vasilis
Thank you for your reply. Looking forward to the FLUKA update.

Lin