Gas-rich Ultra-diffuse Galaxies Are Originated from High Specific Angular Momentum

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Rong, Yu, Hu, Huijie, He, Min, Du, Wei, Guo, Qi, Wang, Hui-Yuan, Zhang, Hong-Xin, Mo, Houjun
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914736310845440
author Rong, Yu
Hu, Huijie
He, Min
Du, Wei
Guo, Qi
Wang, Hui-Yuan
Zhang, Hong-Xin
Mo, Houjun
author_facet Rong, Yu
Hu, Huijie
He, Min
Du, Wei
Guo, Qi
Wang, Hui-Yuan
Zhang, Hong-Xin
Mo, Houjun
contents Ultra-diffuse galaxies, characterized by comparable effective radii to the Milky Way but possessing 100-1,000 times fewer stars, offer a unique opportunity to garner novel insights into the mechanisms governing galaxy formation. Nevertheless, the existing corpus of observational and simulation studies has not yet yielded a definitive constraint or comprehensive consensus on the formation mechanisms underlying ultra-diffuse galaxies. In this study, we delve into the properties of ultra-diffuse galaxies enriched with neutral hydrogen using a semi-analytic method, with the explicit aim of constraining existing ultra-diffuse galaxy formation models. We find that the gas-rich ultra-diffuse galaxies are statistically not failed $L^{\star}$ galaxies nor dark matter deficient galaxies. In statistical terms, these ultra-diffuse galaxies exhibit comparable halo concentration, but higher baryonic mass fraction, as well as higher stellar and gas specific angular momentum, in comparison to typical dwarf galaxy counterparts. Our analysis unveils that higher gas specific angular momentum serves as the underlying factor elucidating the observed heightened baryonic mass fractions, diminished star formation efficiency, expanded stellar disk sizes, and reduced stellar densities in ultra-diffuse galaxies. Our findings make significant contributions to advancing our knowledge of ultra-diffuse galaxy formation and shed light on the intricate interplay between gas dynamics and the evolution of galaxies.
format Preprint
id arxiv_https___arxiv_org_abs_2404_00555
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Gas-rich Ultra-diffuse Galaxies Are Originated from High Specific Angular Momentum
Rong, Yu
Hu, Huijie
He, Min
Du, Wei
Guo, Qi
Wang, Hui-Yuan
Zhang, Hong-Xin
Mo, Houjun
Astrophysics of Galaxies
Ultra-diffuse galaxies, characterized by comparable effective radii to the Milky Way but possessing 100-1,000 times fewer stars, offer a unique opportunity to garner novel insights into the mechanisms governing galaxy formation. Nevertheless, the existing corpus of observational and simulation studies has not yet yielded a definitive constraint or comprehensive consensus on the formation mechanisms underlying ultra-diffuse galaxies. In this study, we delve into the properties of ultra-diffuse galaxies enriched with neutral hydrogen using a semi-analytic method, with the explicit aim of constraining existing ultra-diffuse galaxy formation models. We find that the gas-rich ultra-diffuse galaxies are statistically not failed $L^{\star}$ galaxies nor dark matter deficient galaxies. In statistical terms, these ultra-diffuse galaxies exhibit comparable halo concentration, but higher baryonic mass fraction, as well as higher stellar and gas specific angular momentum, in comparison to typical dwarf galaxy counterparts. Our analysis unveils that higher gas specific angular momentum serves as the underlying factor elucidating the observed heightened baryonic mass fractions, diminished star formation efficiency, expanded stellar disk sizes, and reduced stellar densities in ultra-diffuse galaxies. Our findings make significant contributions to advancing our knowledge of ultra-diffuse galaxy formation and shed light on the intricate interplay between gas dynamics and the evolution of galaxies.
title Gas-rich Ultra-diffuse Galaxies Are Originated from High Specific Angular Momentum
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2404.00555