Stellar models are now approaching predictive levels of accuracy, but the fidelity of these results
depends crucially on the validation of these models. Although we can now reproduce stellar properties
(e.g.\ luminosity) in some evolutionary phases to better than 1\% accuracy, there remain many regimes
where stellar evolution codes do not perform well enough against observations to be informative. To
take full advantage of the breadth, scope, and quality of observational data in the asteroseismic era,
it is critical that our theoretical models improve at pace. The DSEP (Dartmouth Stellar Evolution
Program) and MESA (Modules for Experiments in Stellar Astrophysics) codes are two powerful tools that
serve this purpose: providing high-quality stellar evolution models based on a one-dimensional
formulation of the stellar structure equations, a grid of model atmospheres, and microphysical
considerations.
The focus of my research is the resolution of a number of shortcomings in computational stellar
modeling through use of and contribution to the DSEP and MESA codes.
In this talk, I give a brief overview of the current stellar evolution landscape and present
contributions to several projects dedicated to its improvement. As time allows, topics this talk can
address include:
(1) analysis of synthetic reproductions of the Red Giant Branch Bump using globular cluster data;
(2) empirical calibration of the convective mixing length parameter for metal-poor stars;
(3) development of an interface to convert 1-D MESA stellar density profiles to 3-D particle
distributions which can be used as initial conditions for smoothed-particle hydrodynamics codes such as
GADGET;
(4) attempts to resolve the disparity between classical and asteroseismic observations of the nearby
binary system Alpha Centauri through use of the mixing length as a free parameter; and
(5) development of a locally 2-D MESA module for more accurate calculation of stellar structure
distortion factors used in modeling rapidly rotating stars.
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