Hi!
I am aware that it is highly discouraged to simulate photon sources on OpenMC below ~1keV since there are physical effects in this range not accounted for by the cross-sections library (ENDF). Recently, I happened to notice that the simulations work for some materials at those low energies without an error, which confused me since I thought cross-sections were not available for those energies. I tried to irradiate a Carbon surface with 100eV photon source. I assume those simulations would not be valid as such, but how did the simulation go through without an error?
Regards.