Scattering rate tally

User Support
1

Hello all,

Is it possible to obtain scattering source term using scattering rate tally? I could not find any information about the scattering rate unit. Based on OpenMC documentation, all tally scores are normalized per source. What should I do if the source rate is unknown?

2

Hi @zhangmeithing.zmt,

Thanks for the query!

Regarding the scores units, I’ll point you to the section on scores in the documentation

https://docs.openmc.org/en/stable/usersguide/tallies.html#id2

The "scattering" score is in units of scatter / source-particle like the other reaction rate scores.

As for normalization of this score, I’ll direct you to this section in the documentation on tally normalization

https://docs.openmc.org/en/stable/usersguide/tallies.html#normalization-of-tally-results

Note that for eigenvalue problems this will require additional tallies on the problem to determine the fission rate as well as the heat deposition and number of neutrons emitted per fission event. If you find this section unclear, please reach out for additional info. There’s also an exampl here near the end that you may find useful.

Patrick