Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-12-03
Astronomy and Astrophysics
Astrophysics
14 pages, 28 figures, submitted to MNRAS, higher resolution images can be found at: http://www.cfa.harvard.edu/~schakrab/Spira
Scientific paper
We study the dynamical evolution of spiral structure in the stellar disks of isolated galaxies using high resolution Smoothed Particle Hydrodynamics (SPH) simulations that treat the evolution of gas, stars, and dark matter self-consistently. We focus this study on the question of self-excited spiral structure in the stellar disk and investigate the dynamical coupling between the cold, dissipative gaseous component and the stellar component. We find that angular momentum transport from the gas to the stars inside of corotation leads to a roughly time-steady spiral structure in the stellar disk. To make this point clear, we contrast these results with otherwise identical simulations that do not include a cold gaseous component that is able to cool radiatively and dissipate energy, and find that spiral structure, when it is incipient, dies out more rapidly in simulations that do not include gas. We also employ a standard star formation prescription to convert gas into stars and find that our results hold for typical gas consumption time scales that are in accord with the Kennicutt-Schmidt relation. We therefore attribute the long-lived roughly time steady spiral structure in the stellar disk to the dynamical coupling between the gas and the stars and the resultant torques that the self-gravitating gaseous disk is able to exert on the stars due to an azimuthal phase shift between the collisionless and dissipative components.
No associations
LandOfFree
The Role of Gas In Maintaining Quasi-Steady Spiral Structure In Stellar Disks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Role of Gas In Maintaining Quasi-Steady Spiral Structure In Stellar Disks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Role of Gas In Maintaining Quasi-Steady Spiral Structure In Stellar Disks will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-135343