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arXiv · 2509.21717

MESA Isochrones and Stellar Tracks (MIST) III. The White Dwarf Cooling Sequence

Evan B. Bauer·Aaron Dotter·Charlie Conroy·Tim Cunningham·Minjung Park·Pier-Emmanuel Tremblay
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Abstract

We present a substantial update to the MESA Isochrones and Stellar Tracks (MIST) library, extending the MIST model grids and isochrones down the white dwarf (WD) cooling sequence with realistic physics for WD cooling timescales. This work provides a large grid of MESA models for carbon-oxygen core WDs with hydrogen atmospheres (spectral type DA/DC), descended from full prior stellar evolution calculations. The model tracks, isochrones, and WD cooling timescale contours are available on the MIST project website and at https://doi.org/10.5281/zenodo.15242046. Our WD models provide a very large, publicly available grid with detailed physics for WD cooling timescales: realistic interior and envelope compositions, with element diffusion and heavy-element sedimentation, nuclear burning at the base of the WD hydrogen envelope, core crystallization, and C/O phase separation. As a large grid of open-source stellar evolution models, these WD models provide both out-of-the-box model tracks for comparison with observations and a framework for building further WD models to investigate variations in WD physics.

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Evan B. Bauer, Aaron Dotter, Charlie Conroy, Tim Cunningham, Minjung Park, Pier-Emmanuel Tremblay. 2025-09-26. MESA Isochrones and Stellar Tracks (MIST) III. The White Dwarf Cooling Sequence. https://arxiv.org/abs/2509.21717

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