[mesa-users] Status of OP_a09 tables?

[Ehsan Moravveji]

Hi Warrick,
Two thoughts:
- I am in the process of creating new OP tables calling OP Mono routines, but I have to first understand what I see. It takes some time for me to make sure everything is OK, and it all tests pass, I will generate new tables which anyone can very simply plug into MESA at one’s risk, as Bill said.
- There is a tricky point about the consistency of the opacity tables regarding the Asplund et al. (2009) mixture. In their Sect. 3.12, they give the solar photospheric composition (X, Y, Z) = (0.7381, 0.2485, 0.0134), and the bulk composition (X, Y, Z) = (0.7154, 0.2703, 0.0142).
In chem/public/chem_def.f90, the photospheric abundance is used as the default, while you, as an asteroseismologist adopt this value for the bulk!
Moreover, I have no clue which set of composition was used when computing the OP_a09 tables, because (unfortunately), this is not documented (or I never figured out).
If you’re sensitive to your metal abundance (which I presume you are) in your model, and if they can make significant impact on your seismic tests, you should figure out how to consistently use your mixture with your opacity tables.

Best regards
Ehsan.

> On 27 Jul 2015, at 20:03, Bill Paxton <paxton at kitp.ucsb.edu> wrote:
> 
> Warrick

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