Disks no more: the morphology of low-mass simulated galaxies in FIREbox

2025/08/01 by José A. Benavides, Benavides, José A., Laura V. Sales +21 · 2 voices · 3 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Space Technology and Applications #astro-ph.GA

paper · pdf · doi:10.48550/arxiv.2508.00991

openalex publication_date 2025/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We study the morphology of hundreds of simulated central galaxies in the stellar mass range M_⋆=10^7.5 \rm - 10¹¹~\msun from the FIREbox cosmological volume. We demonstrate that FIREbox is able to predict a wide variety of morphologies, spanning from disk-dominated objects to spheroidal galaxies supported by stellar velocity dispersion. However, the simulations predict a strong relation between morphology (degree of rotational support) and stellar mass: galaxies comparable to the Milky Way are often disk-dominated while the presence of stellar disks mostly vanishes for dwarfs with M_⋆ <10⁹ ~\msun. This defines a ``morphology transition'' regime for galaxies with 10⁹

Cited by

• Igniting galaxy formation in the post-reionization universe
• Disk Formation and the Size-sSFR Relation of Dwarf Galaxies
• CROCODILE-DWARF: Assembly and Kinematics of Field Dwarf Galaxies with GADGET4-OSAKA

Discussions

• Our paper on the emergence of galactic discs has now been accepted for publication (MNRAS). 🔥 📦 🍊 🌀 arxiv.org/abs/2508.00991 [bsky, 10 points, 0 comments]
• Nicole’s first paper looked at the FIREbox sim to see if disks survive in dwarfs! They mostly vanish below M★ ≈ 10⁹ M☉, with a transition at 10⁹–10¹⁰ M☉. Feedback turbulence destroys disks - but a wel [bsky, 4 points, 0 comments]

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