Tabulated nuclear temperature values

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1

Hi all,

I am trying to produce an accurate fission spectrum that is dependent on the isotope. I found the Maxwell fission spectrum equation in the OpenMC documentation, and a way to sample the outgoing neutron energy using Equation (36).
I am still unsure of what is the nuclear temperature T(E) and how to get it. So far from my understanding, it is a tabulated function given in the ENDF library. I currently have the HDF file of the ENDF-VIII from the OpenMC data library. In the HDF file, I found a distribution group for each isotope under reaction_018 (total fission). However, I still can’t figure out what the data under the group represents and how to use them to get the Maxwell Spectrum and Watt Distribution in Equations (36) and (41).

2

The HDF5 file format for nuclear data is documented here. I would give that a look and hopefully that answers your questions about what the data represent. If after looking at that you’re still confused, let me know and I’ll try to help further.