Re: [fluka-discuss]: less than 20 MeV neutrons

From: Santana, Mario <msantana_at_slac.stanford.edu>
Date: Tue, 29 Jul 2014 15:00:07 -0700

Takashi,

Try changing the DEFAULTS SDUM to PRECISIO because NEW-DEFA has a
transport cut-off at 10 MeV and that may be above most of your recoils (?).
Also you can tune the transport threshold with the PART-THR card

Mario

On 7/29/14 10:39 AM, "Maruyama, Takashi" <tvm_at_SLAC.Stanford.EDU> wrote:

>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 Wed Jul 30 2014 - 01:31:07 CEST