So as mentioned during the monthly it’d be nice to have a track-length estimator for photon heating.
(Motivation, better stats.)
How MCNP5/6 handles this (their heating number) is detailed here:
https://mcnp.lanl.gov/pdf_files/la-ur-03-1987.pdf
PDF page 122
Cheers,
Perry
Thanks for the post @yrrepy as well as the link to the relevant section of the MCNP manual. The reason we don’t do a tracklength tally with a heating number for photons, as described in the MCNP manual, is because that’s only valid if thick-target bremsstrahlung is off. The MCNP manual even states further down when talking about equivalence between different tally types that:
For the photon results to be identical, both electron transport and the thick-target bremsstrahlung
approximation (PHYS:P j 1) must be turned off.
To be honest, I don’t know how much the approximation in MCNP will affect accuracy and under what situations, but I think that’s something we’d want to understand before giving an option that gives potentially less accurate answers.
Posting this here for future.
I believe it is a salient document.
(https://www.kns.org/files/int_paper/paper/MC2017_2017_2/P171S02-10LeppanenJ.pdf)
How MCNP5/6 handles this (their heating number) is detailed here:
https://mcnp.lanl.gov/pdf_files/la-ur-03-1987.pdf
PDF page 122
Here is the updated link for everyone coming from the Cardinal discussion:
FYI, there was a photon heating TLE in OpenMC.
It was removed due to issues with brems.
I have restored it and use it in my own OpenMC versions (brems are not an issue for my application).
So the hangup is some mechanics to modify the photon heating number for brems (remove it? add it? don’t have it clear in my mind right now)
