Bibliographic Details
Title: |
HI discs of L$_{\ast}$ galaxies as probes of the baryonic physics of galaxy evolution |
Authors: |
Gensior, Jindra, Feldmann, Robert, Reina-Campos, Marta, Trujillo-Gomez, Sebastian, Mayer, Lucio, Keller, Benjamin W., Wetzel, Andrew, Kruijssen, J. M. Diederik, Hopkins, Philip F., Moreno, Jorge |
Publication Year: |
2023 |
Collection: |
Astrophysics |
Subject Terms: |
Astrophysics - Astrophysics of Galaxies |
More Details: |
Understanding what shapes the cold gas component of galaxies, which both provides the fuel for star formation and is strongly affected by the subsequent stellar feedback, is a crucial step towards a better understanding of galaxy evolution. Here, we analyse the HI properties of a sample of 46 Milky Way halo-mass galaxies, drawn from cosmological simulations (EMP-Pathfinder and FIREbox). This set of simulations comprises galaxies evolved self-consistently across cosmic time with different baryonic sub-grid physics: three different star formation models [constant star formation efficiency (SFE) with different star formation eligibility criteria, and an environmentally-dependent, turbulence-based SFE] and two different feedback prescriptions, where only one sub-sample includes early stellar feedback. We use these simulations to assess the impact of different baryonic physics on the HI content of galaxies. We find that the galaxy-wide HI properties agree with each other and with observations. However, differences appear for small-scale properties. The thin HI discs observed in the local Universe are only reproduced with a turbulence-dependent SFE and/or early stellar feedback. Furthermore, we find that the morphology of HI discs is particularly sensitive to the different physics models: galaxies simulated with a turbulence-based SFE have discs that are smoother and more rotationally symmetric, compared to those simulated with a constant SFE; galaxies simulated with early stellar feedback have more regular discs than supernova-feedback-only galaxies. We find that the rotational asymmetry of the HI discs depends most strongly on the underlying physics model, making this a promising observable for understanding the physics responsible for shaping the interstellar medium of galaxies. Comment: 13 pages, 10 figures + appendices (7 pages, 10 figures); updated to version accepted by MNRAS |
Document Type: |
Working Paper |
Access URL: |
http://arxiv.org/abs/2310.01482 |
Accession Number: |
edsarx.2310.01482 |
Database: |
arXiv |