[Mesa-users] Creating a Highly Irradiated Super-Earth

[Brian Jackson]

Is it possible to revert to a version of MESA that could successfully
navigate these calculations? I see that Chen & Rogers (2016) used
version 7623 to model highly irradiated super-Earths. I was also able
to use an earlier version to do similar calculations.

I know that I can download earlier MESA versions, but the earlier
versions of the SDKs do not appear to be available. Any suggestions?

Thanks,
Brian

On Fri, Jan 24, 2020 at 2:41 PM Brian Jackson <bjackson at boisestate.edu> wrote:
>
> It's actually reassuring. At least I wasn't goofing something up. I'll
> figure out some science workaround.
>
> Thanks very much for the quick response,
> Brian
>
> On Fri, Jan 24, 2020 at 2:37 PM Bill Paxton <paxton at kitp.ucsb.edu> wrote:
> >
> > this is definitely running into EOS problems.  (negative gamma1 -> imaginary sound speed)
> >
> > it may well be related to a blending glitch combining OPAL eos and PC eos.
> >
> > the solution is not likely to be trivial, so don’t hold your breath.
> >
> > we’ll work on it, but it may take some significant time to fix.
> >
> > sorry for the disappointing news.
> >
> > b
> >
> >
> >
> >
> >
> > > On Jan 24, 2020, at 11:53 AM, Brian Jackson <bjackson at boisestate.edu> wrote:
> > >
> > > I've conducted additional experiments, and I think I'm starting to see
> > > what the issues might be.
> > >
> > > I've attached inlists and a model for a slightly different approach.
> > > The model calculation behaves fine until about 4 Gyrs out, when the
> > > timestep suddenly plunges and the code fails to complete the run. For
> > > some reason, the central degeneracy parameter goes haywire shortly
> > > before the run ends -- see attached History_Plot.png.
> > >
> > > Looking at the 2011 MESA instrument
> > > (https://ui.adsabs.harvard.edu/abs/2011ApJS..192....3P/abstract), it
> > > seems the model core may be nearing a transition in the equation of
> > > state (log(density) = -0.19, log(temp) = 3.79 -- see attached Figure
> > > 1). Is there a reason why that transition would severely and abruptly
> > > modify the degeneracy parameter? Is there a way to smooth this
> > > evolutionary phase?
> > >
> > > Or have I completely misunderstood what's going on?
> > >
> > > Thanks,
> > > Brian
> > >
> > > On Wed, Jan 22, 2020 at 5:58 PM Brian Jackson <bjackson at boisestate.edu> wrote:
> > >>
> > >> Dear MESA Users,
> > >> I am still struggling to create highly-irradiated super-Earths using MESA.
> > >>
> > >> I have attached the inlists and saved models I'm using to create a
> > >> 20-Earth mass planet with an envelope mass fraction of 20% (i.e., a
> > >> core mass of 16 Earth masses) and an irradiation 20 times Earth's
> > >> (i.e., 2.72e7 ergs/s/cm^2).
> > >>
> > >> I attempt to create the planet by irradiating a gas giant planet and
> > >> then relaxing the mass down to my desired mass. (I've found doing it
> > >> the other way around leads to badness.) I've tried tweaking lots of
> > >> settings, but nothing seems to work. In the end, I wind up with a
> > >> timestep below the suggested minimum of 9.9999999999999995D-07.
> > >>
> > >> I am using Mac OS 10.13.1, MESA 11701, and the most recent version of
> > >> the SDK (August 30 2019).
> > >>
> > >> Please forgive me if I forgot any required information.
> > >>
> > >> Thanks,
> > >> Brian
> > > <inlist><inlist_pgstar><history_columns.list><LF14_planet_relaxedM_20_ME_10-percent.mod><Paxton2011_Fig1.png><History_Plot.png>_______________________________________________
> > > mesa-users at lists.mesastar.org
> > > https://lists.mesastar.org/mailman/listinfo/mesa-users
> > >
> >