Saved in:
Bibliographic Details
Main Authors: Laing, Jennifer M., Wilson, Christine D.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2510.17768
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918164241055744
author Laing, Jennifer M.
Wilson, Christine D.
author_facet Laing, Jennifer M.
Wilson, Christine D.
contents Work by the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) collaboration found higher molecular gas surface densities and velocity dispersions in the centres of barred galaxies compared to unbarred galaxies. We explore central molecular gas using published high resolution (150 pc) measurements of CO$(2-1)$ from the PHANGS-ALMA survey and a new velocity dispersion-dependent prescription for the CO-to-H$_{2}$ conversion factor $α_{\rm{CO}}$. Comparisons of the molecular gas surface density, velocity dispersion, star formation rate, and depletion time reveal that these quantities are different in the centres of barred and unbarred galaxies. Gas depletion times are found to be shorter in barred galaxy centres. Even when we control for the presence of an AGN, the velocity dispersion and depletion time are found to be statistically different between barred and unbarred galaxy centres. The higher velocity dispersion suggests extra non-circular motions, possibly due to the inflow of gas along the bar, that are not constant but must increase as the star formation rate increases.
format Preprint
id arxiv_https___arxiv_org_abs_2510_17768
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Increased molecular gas velocity dispersion and star formation efficiency in barred galaxy centres
Laing, Jennifer M.
Wilson, Christine D.
Astrophysics of Galaxies
Work by the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) collaboration found higher molecular gas surface densities and velocity dispersions in the centres of barred galaxies compared to unbarred galaxies. We explore central molecular gas using published high resolution (150 pc) measurements of CO$(2-1)$ from the PHANGS-ALMA survey and a new velocity dispersion-dependent prescription for the CO-to-H$_{2}$ conversion factor $α_{\rm{CO}}$. Comparisons of the molecular gas surface density, velocity dispersion, star formation rate, and depletion time reveal that these quantities are different in the centres of barred and unbarred galaxies. Gas depletion times are found to be shorter in barred galaxy centres. Even when we control for the presence of an AGN, the velocity dispersion and depletion time are found to be statistically different between barred and unbarred galaxy centres. The higher velocity dispersion suggests extra non-circular motions, possibly due to the inflow of gas along the bar, that are not constant but must increase as the star formation rate increases.
title Increased molecular gas velocity dispersion and star formation efficiency in barred galaxy centres
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2510.17768