Mass models of disk galaxies from gas dynamics
Abstract
I review methods and techniques to build mass models of disk galaxies from gas dynamics. I focus on two key steps: (1) the derivation of rotation curves using 3D emission-line datacubes from HI, CO, and/or H-alpha observations, and (2) the calculation of the gravitational field from near-infrared images and emission-line maps, tracing the stellar and gas mass distributions, respectively. Mass models of nearby galaxies led to the establishment of the radial acceleration relation (RAR): the observed centripetal acceleration from rotation curves closely correlates with that predicted from the baryonic distribution at each galaxy radius, even when dark matter supposedly dominates the gravitational field. I conclude by discussing the (uncertain) location of Local Group dwarf spheroidal galaxies on the RAR defined by more massive disk galaxies.
Keywords
Cite
@article{arxiv.2305.18224,
title = {Mass models of disk galaxies from gas dynamics},
author = {Federico Lelli},
journal= {arXiv preprint arXiv:2305.18224},
year = {2026}
}
Comments
Invited Review for the IAU Symposium 379 "Dynamical Masses of Local Group Galaxies" (10 pages, 2 figures)