[mesa-users] Reporting on a Slow Run with Paczynski_grey Atmosphere

[Jakub Ostrowski]

Hi Ehsan!

I tried to use Paczynski_grey when I started using MESA and I very quickly realized that you can't use it in PMS phase. Notice two things: this atmosphere model uses MLT  and PMS stars are almost entirely convective. First models look like one big convective atmosphere and this is probably the reason why there are convergence issues.

You can use it if you start from ZAMS but in this case I had convergence issues when a star reaches RGB so I eventually opted for 'Eddington_grey' because the impact on HR diagram was irrelevant.

There is irony here because Paczynski developed this model of atmosphere mainly for red giants :D

Take care,
Jakub