Dear FLUKA experts,
I’m currently working on a simulation of electrons hitting a tungsten target and then producing neutrons. I want to know the energy flux spectrum of the neutrons produced by the tungsten target, so I’m using USRBDX, which, as explained in the FLUKA manual, counts the flux at the cross-interface, so USRBDX should be able to accomplish this task. I also used USRBDX (24 BIN). But the result is not what I expected. So I also performed the same calculation using MCNP and found that the results from MCNP were not consistent with the results from FLUKA, but the results from MCNP were as I expected.
So I would like to ask the experts why is this?
Especially in the low-energy neutron part, the MCNP and FLUK results are completely different. I know there are errors in the flux statistics, but the difference between the two is so large that it’s beyond what can be explained by the errors. I’m wondering if it’s because of any problems with the input card settings in FLUKA? Thanks to the experts for their replies and clarifications.
You are just doing a wrong plot, where you get dN/dE [=Y] instead of dN/dlogE [=<X>*Y], as it should be on a logarithmic energy [ X ] scale. Read carefully slides 43-49.
