I’m trying to post-processing some microscopic cross section and I’m also interested in the (n,level) reaction, MT=4, which should correspond to the sum of all other inelastic reactions (n,nX).
Despite the correct computation for few isotopes, the vast majority of isotopic cross sections obtained for this reaction are equal to zero, although the (n,Xn) reactions for the same isotopes display not zero values.
I would like to understand if somebody has any clues regarding this problem, and how to solve it without scoring all 40 (n,Xn) cross sections and then performing a sum.
Hi!
I recently encountered the same problem while estimating the inelastic scattering of Lead.
It seems OpenMC is incapable of scoring MT 4 if reaction_4 is not present in the “isotope.h5” file.
By looking inside the hdf5 files, I’ve observed that reaction_4 is present for some isotopes such as B10, but it is not for the isotopes of Lead.
It’s true, scoring can only happened if the reactions present in the cross-section data. While ENDF doesn’t have all the reactions, TENDL might have it.
Try use TENDL.
Edit after i read the first reply:
It’s probably the consequence of how from_njoy works or something…
Hi!
Thanks for your feedback!
I’ve played a bit with ENDFtk and I’ve seen that the ENDF files of Lead have MT4!
On the other hand, it is not present neither in the ACE file, nor in the HDF5 file.
I think this issue is more related to the processing made by NJOY rather then OpenMC.