pith. sign in

Breathing FIRE: How Stellar Feedback Drives Radial Migration, Rapid Size Fluctuations, and Population Gradients in Low-Mass Galaxies

5 Pith papers cite this work. Polarity classification is still indexing.

5 Pith papers citing it
abstract

We examine the effects of stellar feedback and bursty star formation on low-mass galaxies ($M_{\rm star}=2\times10^6-5\times10^{10}{\rm M_{\odot}}$) using the FIRE (Feedback in Realistic Environments) simulations. While previous studies emphasized the impact of feedback on dark matter profiles, we investigate the impact on the stellar component: kinematics, radial migration, size evolution, and population gradients. Feedback-driven outflows/inflows drive significant radial stellar migration over both short and long timescales via two processes: (1) outflowing/infalling gas can remain star-forming, producing young stars that migrate $\sim1{\rm\,kpc}$ within their first $100 {\rm\,Myr}$, and (2) gas outflows/inflows drive strong fluctuations in the global potential, transferring energy to all stars. These processes produce several dramatic effects. First, galaxies' effective radii can fluctuate by factors of $>2$ over $\sim200 {\rm\,Myr}$, and these rapid size fluctuations can account for much of the observed scatter in radius at fixed $M_{\rm star}.$ Second, the cumulative effects of many outflow/infall episodes steadily heat stellar orbits, causing old stars to migrate outward most strongly. This age-dependent radial migration mixes---and even inverts---intrinsic age and metallicity gradients. Thus, the galactic-archaeology approach of calculating radial star-formation histories from stellar populations at $z=0$ can be severely biased. These effects are strongest at $M_{\rm star}\approx10^{7-9.6}{\rm M_{\odot}}$, the same regime where feedback most efficiently cores galaxies. Thus, detailed measurements of stellar kinematics in low-mass galaxies can strongly constrain feedback models and test baryonic solutions to small-scale problems in $\Lambda$CDM.

years

2026 5

verdicts

UNVERDICTED 5

clear filters

representative citing papers

Non-linear Dynamical Stability of Magnetic Polytropes

astro-ph.SR · 2026-05-30 · unverdicted · novelty 5.0

A mean-field magnetic polytrope model shows radiation pressure can unbind an n=3 polytrope when the central overpressure exceeds roughly 0.15 times a mass-dependent factor under small radial perturbations.

Probing the faint end of simulated galaxy counts at z>3

astro-ph.CO · 2026-05-15 · unverdicted · novelty 5.0

TNG100 and EAGLE hydrodynamical simulations underproduce faint compact galaxies at z>3 relative to CANDELS observations even after forward modeling and completeness corrections, with the mismatch linked to both detection effects and simulation physics.

The Bright Future of the Dark and Dim Universe

astro-ph.GA · 2026-06-25 · unverdicted · novelty 2.0

Review chapter on SKA observations of RELHICs and dim galaxies to constrain LambdaCDM and baryonic physics via HIMF, HIVF, and bTFR down to 10^6 solar masses.

citing papers explorer

Showing 1 of 1 citing paper after filters.

  • Non-linear Dynamical Stability of Magnetic Polytropes astro-ph.SR · 2026-05-30 · unverdicted · none · ref 140 · internal anchor

    A mean-field magnetic polytrope model shows radiation pressure can unbind an n=3 polytrope when the central overpressure exceeds roughly 0.15 times a mass-dependent factor under small radial perturbations.