Dear All
I am using source.f and mgdraw.f to emit a beam of thermal neutrons onto a sheet of cadmium. The resultant gammas pair produce in Tungsten mesh. The positron KE at the instant of pair production is recorded by the mgdraw.f code.
I noticed that I get error message (positron_maker005.err (86.0 KB) )whenever I increase the beam energy in the BEAM card. At lower energies (<= 1e-8 GeV) there is no problem. Can someone please explain the reason? Is it because the energy limit, as set by BEAM card, is more than the energies that I am sampling?
sincerely
saurabh
The content of spectrum.dat file that I use in source.f----
1E-14 0
2E-14 2
4E-14 4
1.6E-13 16
1E-12 121
5E-12 417
2E-11 902
1E-10 23
3E-10 0.06
6.5E-10 2E-7
The reason that you only get the error at higher energies can be explained easily.
FLUKA doesn’t see geometry errors, unless a particle it trying to enter an the problematic (overlapping or undefined) part of the geometry.
At low energies, most likely all particles stopped or scattered away from the error. While higher energies, it is more likely, that particles pass straight trough your geometry, reaching the error.
Dear David
thanks for the answer. that cleared things up. Just to confirm one more thing. the energy in the BEAM card should be more than the energy being sampled by the source.f routine? Is this correct?
sincerely
saurabh