Hi all,
I’m trying to simulate a rather simple case of photon induced fission on a bare Uranium sphere (natural composition), with the photon source uniformly distributed within the sphere. The photon energies are binned 100 groups between 1 and 20 MeV (linear steps), with equal probability.
With coupled neutron-photon transport I tried tallies on the spatial distribution of photon flux, neutron flux, fission rate (keyword ‘fission’) and fission neutron yield (keyword ‘nu-fission’).
While I do see photon flux, the tallies on neutron flux and fission all give 0 ± 0 as if no event is produced.
Do you have any idea on the issue? Maybe I can do tallies on (gamma,n) with another score?
Thank you in advance,