lowT kap returns NaNs for temperatures below the table boundary
Closed this issue · 3 comments
See https://lists.mesastar.org/pipermail/mesa-users/2023-July/014625.html, Is this diagnosis correct?
It appears that at temperatures below the lower edge of the lowT molecular opacity tables(e.g. logT < 2.7d0 for fa05_gs98) the kap module is returning NaNs? This is an uncommon place for a model to live, but for very low mass models this could be an issue?
Should a conditional statement be added to check if the temperature of a zone decreases beyond the lower edge of the table, so the opacity can be extrapolated in this regime or is it and intensional measure to let the code crash here? Please let me know if I'm missing something.
You can make custom molecular opacities with AESOPUS that extend further than logT=2.7. If people are modelling in the low mass regime, I would be encouraging them to make their own tables with CNO enhancements (not included with fa05) appropriate for their regime, rather than trying to extrapolate Ferguson any further.
Thanks Giulia! In that case, Instead of making any changes to kap, I think some documentation in the Kap section explaining this could be warranted?
Ignore my previous statement. I think the discussion in the kap section right now is sufficient, and people could easily opt for AESOPUS or the low T Freedman tables (1.88) as explained in the low T kap section. I will close this thread now.