Score only the primary neutron,excluding fission neutron.

Dear FLUKA experts:

      Please help me with my problem. Thanks.

      In my model, the source particle is neutron, emiting from the fuel
assembly in the middle. Water and iron surround the fuel assembly. I want to
score the fluence of neutron in the iron.

      I want to score only the source neutron or called primary neutron,
excluding fission neutron. Namely, I don't want secondary neutron to be
transported and scored. Or, I want to switch off fission. What can I do with
FLUKA?

      As I know, in MCNP, there is a NONU card, Fission Turnoff Card. This
card turns off fission in a cell. The fission is then treated as simple
capture.

      The following is my thoughts, which I have tried and got no effect.

      (1)If WHAT(6) of LOW-NEUT is 0.0,is fission neutron multiplicity forced
to 0?

      (2)In user routines MDSTCK(management of the stack of secondaries),
         NUMSEC is number of secondary particles produced in the interaction,
         can I just NUMSEC=0?
Received on Mon Feb 20 2012 - 10:28:36 CET