Mass distributions in disk galaxies

Thomas Martinsson, Marc Verheijen, Matthew Bershady, Kyle Westfall, David Andersen, Rob Swaters



We present results on luminous and dark matter mass distributions in disk galaxies from the DiskMass Survey. As expected for normal disk galaxies, stars dominate the baryonic mass budget in the inner region of the disk; however, at about four optical scale lengths (hR ) the atomic gas starts to become the dominant contributor. Unexpectedly, we find the total baryon to dark-matter fraction within a galaxy stays nearly constant with radius from 1hR out to at least 6hR , with a baryon fraction of 15-50% among galaxies. On average, only one third of the mass within 2.2hR in a disk galaxy is baryonic and these baryons appear to have had only a minor effect on the distribution of the dark matter.
Originele taal-2English
Pagina's (van-tot)283
Aantal pagina's1
TijdschriftFormation and Evolution of Galaxy Outskirts, Proceedings of the International Astronomical Union, IAU Symposium
StatusPublished - mrt.-2016

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