Stromlo Stellar Tracks: non-solar scaled abundances for massive stars
  We present the Stromlo Stellar Tracks, a set of stellar evolutionary tracks,
computed by modifying the Modules for Experiments in Stellar Astrophysics
(MESA) 1D stellar evolution package, to fit the Galactic Concordance abundances
for hot ($T > 8000$ K) massive ($\geq 10M_\odot$) Main-Sequence (MS) stars.
Until now, all stellar evolution tracks are computed at solar, scaled-solar, or
alpha-element enhanced abundances, and none of these models correctly represent
the Galactic Concordance abundances at different metallicities. This paper is
the first implementation of Galactic Concordance abundances to the stellar
evolution models. The Stromlo tracks cover massive stars ($10\leq M/M_\odot
\leq 300$) with varying rotations ($v/v_{\rm crit} = 0.0, 0.2, 0.4$) and a
finely sampled grid of metallicities ($-2.0 \leq {\rm [Z/H]} \leq +0.5$;
$\Delta {\rm [Z/H]} = 0.1$) evolved from the pre-main sequence to the end of
$^{12}$Carbon burning. We find that the implementation of Galactic Concordance
abundances is critical for the evolution of main-sequence, massive hot stars in
order to estimate accurate stellar outputs (L, T$_{\rm eff}$, $g$), which, in
turn, have a significant impact on determining the ionizing photon luminosity
budgets. We additionally support prior findings of the importance that rotation
plays on the evolution of massive stars and their ionizing budget. The
evolutionary tracks for our Galactic Concordance abundance scaling provide a
more empirically motivated approach than simple uniform abundance scaling with
metallicity for the analysis of HII regions and have considerable implications
in determining nebular emission lines and metallicity. Therefore, it is
important to refine the existing stellar evolutionary models for comprehensive
high-redshift extragalactic studies. The Stromlo tracks are publicly available
to the astronomical community online.
