Spatially-resolved galaxy angular momentum
Abstract
The total specific angular momentum j of a galaxy disk is matched with that of its dark matter halo, but the distributions are different, in that there is a lack of both low- and high-j baryons with respect to the CDM predictions. I illustrate how the probability density function PDF(j/j_mean) can inform us of a galaxy's morphology and evolutionary history with a spanning set of examples from present-day galaxies and a galaxy at z~1.5. The shape of PDF(j/j_mean) is correlated with photometric morphology, with disk-dominated galaxies having more symmetric PDF(j/j_mean) and bulge-dominated galaxies having a strongly-skewed PDF(j/j_mean). Galaxies with bigger bulges have more strongly-tailed PDF(j/j_mean), but disks of all sizes have a similar PDF(j/j_mean). In future, PDF(j/j_mean) will be useful as a kinematic decomposition tool.
Cite
@article{arxiv.1808.06269,
title = {Spatially-resolved galaxy angular momentum},
author = {Sarah M. Sweet and Deanne B. Fisher and Karl Glazebrook and Danail Obreschkow and Claudia D. P. Lagos and Liang Wang},
journal= {arXiv preprint arXiv:1808.06269},
year = {2018}
}
Comments
Invited feature talk at IAU Focus Meeting 6; to appear in proceedings Astronomy in Focus