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arXiv · 1808.06269

Spatially-resolved galaxy angular momentum

Sarah M. Sweet·Deanne B. Fisher·Karl Glazebrook·Danail Obreschkow·Claudia D. P. Lagos·Liang Wang
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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.

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Sarah M. Sweet, Deanne B. Fisher, Karl Glazebrook, Danail Obreschkow, Claudia D. P. Lagos, Liang Wang. 2018-08-19. Spatially-resolved galaxy angular momentum. https://arxiv.org/abs/1808.06269

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