English

Exploring the Angular Momentum -- Atomic Gas Content Connection with EAGLE and IllustrisTNG

Astrophysics of Galaxies 2023-09-19 v3

Abstract

We use the EAGLE (Evolution and Assembly of GaLaxies and their Environments) and IllustrisTNG (The Next Generation) cosmological simulations to investigate the properties of the baryonic specific angular momentum (j), baryonic mass (M) and atomic gas fraction (fatmf_{\rm{atm}}) plane for nearby galaxies. We find EAGLE and TNG to be in excellent agreement with each other. These simulations are also consistent with the results obtained with xGASS (eXtended GALEX Arecibo SDSS Survey) for gas fractions greater than 0.01. This implies that the disagreements previously identified between xGASS and predictions from simple analytical disc stability arguments also holds true for EAGLE and TNG. For lower gas fraction (the regime currently unconstrained by observations), both simulations deviate from the plane but still maintain good agreement with each other. Despite the challenges posed by resolution limits at low gas fractions, our findings suggest a potential disconnect between angular momentum and gas fraction in the gas-poor regime, implying that not all gas-poor galaxies have low specific angular momentum.

Keywords

Cite

@article{arxiv.2307.02722,
  title  = {Exploring the Angular Momentum -- Atomic Gas Content Connection with EAGLE and IllustrisTNG},
  author = {Jennifer A. Hardwick and Luca Cortese and Danail Obreschkow and Claudia Lagos and Adam R. H. Stevens and Barbara Catinella and Lilian Garratt-Smithson},
  journal= {arXiv preprint arXiv:2307.02722},
  year   = {2023}
}

Comments

12 pages, 10 figures. Accepted for publication in MNRAS

R2 v1 2026-06-28T11:23:18.431Z