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arXiv · 1311.7207

Scaling laws in disk galaxies

Alister W. Graham
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Abstract

A brief overview of several recent disk galaxy scaling relations is presented, along with some historical background. In particular, after introducing the (basic) radial light profiles of disk galaxies, I explain several important `structural' scaling relations and review the latest bulge-(black hole mass) diagrams. I go on to present the typical bulge-to-disk flux ratios of disk galaxies and suggest the use of a grid of bulge-to-disk flux ratio versus disk Hubble type - based on the nature of the spiral arms - to complement the Hubble-Jeans sequence. I then briefly mention pure disk galaxies before cautioning on difficulties with identifying pseudo-bulges built from secular evolution. Finally, I conclude by discussing a likely connection between modern day bulges in disk galaxies and high-redshift (z ~ 2+/-0.5) compact galaxies which may have since acquired a disk via cold flows and quiescent accretion.

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Alister W. Graham. 2013-11-28. Scaling laws in disk galaxies. https://arxiv.org/abs/1311.7207

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