[fluka-discuss]: less than 20 MeV neutrons

From: Maruyama, Takashi <tvm_at_slac.stanford.edu>
Date: Tue, 29 Jul 2014 10:39:57 -0700

I am trying to find energy deposition in a 320 micron-thick Silicon layer from incident neutrons. The neutron energy is monochromatic and set by the BEAM card. When I use the energy density per region in .out file, everything looks good; the energy deposition varies smoothly at 20 MeV. I wanted to find what particles are contributing to the energy depositions. So I use mgdraw to dump these particles. Above 20 MeV neutron incident, I see many recoil protons, 4He and some e-'s contributing to the energy deposition. However, as soon as I cross 20 MeV neutron energy, these recoil protons and 4He disappear, and only e-'s are present. There must be a switch or threshold for recoil particle tracking, but I cannot figure out what. Please help.

Takashi Maruyama
SLAC
Received on Tue Jul 29 2014 - 21:01:29 CEST