app_mesa.tex

The MESA EOS is a blend of the OPAL \citep{Rogers2002}, SCVH
\citep{Saumon1995}, FreeEOS \citep{Irwin2004}, HELM \citep{Timmes2000},
PC \citep{Potekhin2010}, and Skye \citep{Jermyn2021} EOSes.

Radiative opacities are primarily from OPAL \citep{Iglesias1993,
IglesiasRogers1996}, with low-temperature data from \citet{Ferguson2005}
and the high-temperature, Compton-scattering dominated regime by
\citet{Poutanen2017}.  Electron conduction opacities are from
\citet{Cassisi2007}.

Nuclear reaction rates are from JINA REACLIB \citep{Cyburt2010}, NACRE \citep{Angulo1999} and
additional tabulated weak reaction rates \citet{Fuller1985, Oda1994,
Langanke2000}.  Screening is included via the prescription of \citet{Chugunov2007}.
Thermal neutrino loss rates are from \citet{Itoh1996}.


We create 1D stellar models and evolve them from the pre-main sequence until roughly the end of hydrogen shell burning.
We study stellar masses between 0.9 and 1.7 $M_{\odot}$ in steps of $0.2 M_{\odot}$. We study metallicities [Fe/H] ranging from -1.4 to 0.4 in steps of 0.2 dex. To convert from metallicity units to MESA input $Y$ and $Z$ units, we assume a linear helium enrichment law \citep[per e.g.,][sec 3.1]{choi2016} in which we adopt a Big-Bang $Y_p = 0.2485$ and $\Delta Y / \Delta Z = 1.3426$ according to Table 1 of \citet{tayar_etal_2022}. The algorithm we use to calculate $X$, $Y$, and $Z$ from these values is identical to the one used in \url{https://github.com/aarondotter/initial_xa_calculator}; we \textbf{adopt the solar heavy element mixture of} \citet{GrevesseSauval1998}.
%and [$\alpha$/Fe].
The specific [Fe/H] to ($X$, $Y$, $Z$) conversions used here are shown in Table~\ref{table:feh_to_z}.

\begin{deluxetable}{c c c c}
\caption{
     Mappings between $[$Fe/H$]$ values and MESA input values of $(X, Y, Z)$.}
    \label{table:feh_to_z}
\tablehead{
\colhead{[Fe/H]} & \colhead{$X$} & \colhead{$Y$} & \colhead{$Z$}
}
\decimals
\startdata
      0.400 & 0.66214302 & 0.29971262 & 0.03814436 \\
      0.200 & 0.69253197 & 0.28229599 & 0.02517204 \\
      0.000 & 0.71318414 & 0.27045974 & 0.01635613 \\
     -0.200 & 0.72686070 & 0.26262137 & 0.01051793 \\
     -0.400 & 0.73576323 & 0.25751912 & 0.00671765 \\
     -0.600 & 0.74149343 & 0.25423501 & 0.00427157 \\
     -0.800 & 0.74515509 & 0.25213642 & 0.00270849 \\
     -1.000 & 0.74748410 & 0.25080161 & 0.00171429 \\
     -1.200 & 0.74896112 & 0.24995509 & 0.00108379 \\
     -1.400 & 0.74989606 & 0.24941926 & 0.00068468
\enddata
%\begin{caption}

%\end{caption}
\end{deluxetable}