I am trying to simulate energy deposited by Fission Fragments in a test Fission Chamber made up of U238. I am using DETECT card to understand how energy is deposited by each event in the coating material or ionising gas. In the U238 coating material, the max deposited energy per event goes up to ~400 MeV. Is it due to fission created by secondary neutrons? If so, can I score the number of fission produced by primary and secondary neutrons separately?
Additionally, I understand from the documentation that FLUKA currently models only prompt neutrons in fission processes and does not explicitly simulate delayed neutron emission. Could you please confirm if this is still the case?
With your DETECT card, you are scoring the energy deposition per event, where “event” refers to the energy deposited in one or more DETECTOR REGIONS by one primary particle and its descendants (continues on the manual).
Therefore, yes, primaries and all kind of secondaries (including particles emerging from fission, like energetic fission fragments) contribute to your scoring.
Regarding obtaining information about fissions caused by primary or secondary particles:
The output file contains a section titled “Run Summary” that provides some statistics about the simulation (number of stars, number of secondaries in stars, etc.). I’m not sure whether this information will be sufficient for your needs.
If it’s not, I believe one viable solution is to use the mgdraw user routine. While this requires a non-standard implementation, it gives you access to a wide range of transport variables, allowing you to potentially filter and count the specific quantities you’re interested in.
I’ll leave here the advanced course lecture on mgdraw, as well as a forum post that you may find useful.
Finally, your last query: the last advanced and beginner FLUKA courses confirm your statement. I will cross check with colleagues and come back to you in case of different information/developments.
Does it mean the 46th Fission event was produced by a neutron which is in it’s 13th generation by any type of interaction and it produces 2 prompt fission neutrons where as 49th event was produced by a primary neutron and it produced 5 prompt fission neutrons ?
