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Title: FIRE-3: updated stellar evolution models, yields, and microphysics and fitting functions for applications in galaxy simulations

Increasingly, uncertainties in predictions from galaxy formation simulations (at sub-Milky Way masses) are dominated by uncertainties in stellar evolution inputs. In this paper, we present the full set of updates from the Feedback In Realistic Environment (FIRE)-2 version of the FIRE project code, to the next version, FIRE-3. While the transition from FIRE-1 to FIRE-2 focused on improving numerical methods, here we update the stellar evolution tracks used to determine stellar feedback inputs, e.g. stellar mass-loss (O/B and AGB), spectra (luminosities and ionization rates), and supernova rates (core-collapse and Ia), as well as detailed mass-dependent yields. We also update the low-temperature cooling and chemistry, to enable improved accuracy at $T \lesssim 10^{4}\,$K and densities $n\gg 1\, {\rm cm^{-3}}$, and the meta-galactic ionizing background. All of these synthesize newer empirical constraints on these quantities and updated stellar evolution and yield models from a number of groups, addressing different aspects of stellar evolution. To make the updated models as accessible as possible, we provide fitting functions for all of the relevant updated tracks, yields, etc, in a form specifically designed so they can be directly ‘plugged in’ to existing galaxy formation simulations. We also summarize the default FIRE-3 implementations of ‘optional’ physics, including spectrally resolved cosmic rays and supermassive black hole growth and feedback.

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Award ID(s):
1910346 2108962 1752913 2108230 1715216 2108318 1715847 1713353 2107772 2045928 2009687 2107872
Author(s) / Creator(s):
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Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Medium: X Size: p. 3154-3181
["p. 3154-3181"]
Sponsoring Org:
National Science Foundation
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