[Mesa-users] Mesastar Question: Setting Initial CO Abudance Enhancements

[Evan Bauer]

Hi Kayla,

To respond to your questions about the aFe opacity tables...
>  have had a look at the tables available in data/kap_data and the closest one to my case is 'gs98_aFe_p2_z0.004_x0.7.data' (however I need initial values of Z=0.008, Y=0.26, X=0.732). How would I go about creating a similar .data table (i.e., one with  [alpha/Fe]=0.2) for my required z and x initial composition values instead? 
> Additionally, I don't think I am quite understanding what the values listed for user_kap_Xs and user_kap_Zs are. Could you elaborate on what they correspond to? 
The opacity tables provide enough coverage of composition in X,Z space (with Y=1-X-Z) that they can interpolate to an opacity for any combination of X,Y,Z. You just have to specify what metal mixture makes up "Z", which is what the gs98_aFe_p2 prefix takes care of. What you see in the data/kap_data folder is lots of opacity tables covering all of composition space for a gs98_aFe_p2 mixture, and MESA will take care of tracking the composition of each zone for opacity calls and interpolating across the relevant tables. That's also part of the answer to your other question about "user_kap_Xs" and "user_kap_Zs". Because MESA treats these aFe tables as "custom" user tables, you need to tell it what number of points in X and Z space are covered by the various files, and what values of X,Z are represented for interpolating across those tables.

Cheers,
Evan

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