The Stability of Galaxy Disks

K. B. Westfall, D. R. Andersen, M. A. Bershady, T. P. K. Martinsson, R. A. Swaters, M. A. W. Verheijen

OnderzoeksoutputAcademicpeer review


We calculate the stellar surface mass density (Σ*) and two-component (gas+stars) disk stability (QRW) for 25 late-type galaxies from the DiskMass Survey. These calculations are based on fits of a dynamical model to our ionized-gas and stellar kinematic data performed using a Markov Chain Monte Carlo sampling of the Bayesian posterior. Marginalizing over all galaxies, we find a median value of QRW = 2.0±0.9 at 1.5 scale lengths. We also find that QRW is anti-correlated with the star-formation rate surface density (Σ*), which can be predicted using a closed set of empirical scaling relations. Finally, we find that the star-formation efficiency (Σ*/Σg) is correlated with Σ* and weakly anti-correlated with QRW. The former is consistent with an equilibrium prediction of Σ*/Σg ∝ Σ*1/2. Despite its order-of-magnitude range, we find no correlation of Σ*/ΣgΣ*1/2 with any other physical quantity derived by our study.
Originele taal-2English
TitelStructure and Dynamics of Disk Galaxies
SubtitelProceedings of the Conference held 12-16 August, 2013 at the Winthrop Rockefeller Institute, Petit Jean Mountain, Arkansas, USA
RedacteurenM.S. Seigar, P. Treuthardt
StatusPublished - 1-mrt-2014
EvenementStructure and Dynamics of Disk Galaxies - , United Kingdom
Duur: 12-aug-201316-aug-2013

Publicatie series

NaamASP Conference Series


ConferenceStructure and Dynamics of Disk Galaxies
Land/RegioUnited Kingdom

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