Second public data release of the FIRE-2 cosmological zoom-in simulations of galaxy formation

Andrew Wetzel; Jenna Samuel; Pratik J. Gandhi; Sam B. Ponnada; Kung-Yi Su; Arpit Arora; Daniel Angles-Alcazar; Christopher C. Hayward; Robyn E. Sanderson; Robert Feldmann; Rachel Cochrane; Farnik Nikakhtar; Nondh Panithanpaisal; Jose A. Benavides; Viraj Pandya; Mike Grudic; Cameron Hummels; Alexander B. Gurvich; Zachary Hafen; Xiangcheng Ma; Shea Garrison-Kimmel; Omid Sameie; T. K Chan; Kareem El-Badry; Lina Necib; Sarah Loebman; Sarah Wellons; Victor H. Robles; Coral Wheeler; Jorge Moreno; Jonathan Stern; Michael Boylan-Kolchin; James S. Bullock; Claude-Andre Faucher-Giguere; Dusan Keres; Eliot Quataert; Philip F. Hopkins

arXiv · 2508.06608

Second public data release of the FIRE-2 cosmological zoom-in simulations of galaxy formation

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Abstract

We describe the second data release (DR2) of the FIRE-2 cosmological zoom-in simulations of galaxy formation, from the Feedback In Realistic Environments (FIRE) project, available at http://flathub.flatironinstitute.org/fire. DR2 includes all snapshots for most simulations, starting at z ~ 99, with all snapshot time spacings <~ 25 Myr. The Core suite -- comprising 14 Milky Way-mass galaxies, 5 SMC/LMC-mass galaxies, and 4 lower-mass galaxies -- includes 601 snapshots to z = 0. For the Core suite, we also release resimulations with physics variations: (1) dark-matter-only versions; (2) a modified ultraviolet background with later reionization at z = 7.8; (3) magnetohydrodynamics, anisotropic conduction, and viscosity in gas; and (4) a model for cosmic-ray injection, transport, and feedback (assuming a constant diffusion coefficient). The Massive Halo suite now includes 8 massive galaxies with 278 snapshots to z = 1. The High Redshift suite includes 34 simulations: in addition to the 22 simulations run to z = 5, we now include 12 additional simulations run to z = 7 and z = 9. We also release 4 dark-matter-only cosmological boxes used to generate zoom-in initial conditions for many FIRE simulations. Most simulations include catalogs of (sub)halos and galaxies at all available snapshots, and most Core simulations to z = 0 include full halo merger trees.

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Andrew Wetzel, Jenna Samuel, Pratik J. Gandhi, Sam B. Ponnada, Kung-Yi Su, Arpit Arora, Daniel Angles-Alcazar, Christopher C. Hayward, Robyn E. Sanderson, Robert Feldmann, Rachel Cochrane, Farnik Nikakhtar, Nondh Panithanpaisal, Jose A. Benavides, Viraj Pandya, Mike Grudic, Cameron Hummels, Alexander B. Gurvich, Zachary Hafen, Xiangcheng Ma, Shea Garrison-Kimmel, Omid Sameie, T. K Chan, Kareem El-Badry, Lina Necib, Sarah Loebman, Sarah Wellons, Victor H. Robles, Coral Wheeler, Jorge Moreno, Jonathan Stern, Michael Boylan-Kolchin, James S. Bullock, Claude-Andre Faucher-Giguere, Dusan Keres, Eliot Quataert, Philip F. Hopkins. 2025-08-08. Second public data release of the FIRE-2 cosmological zoom-in simulations of galaxy formation. https://arxiv.org/abs/2508.06608

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