Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2012-02-28
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
12 pages, 14 figures
Scientific paper
We run N-body smoothed particle hydrodynamics (SPH) simulations of a Milky Way sized galaxy. The code takes into account hydrodynamics, self-gravity, star formation, supernova and stellar wind feedback, radiative cooling and metal enrichment. The simulated galaxy is a barred-spiral galaxy consisting of a stellar and gas disc, enveloped in a static dark matter halo. Similar to what is found in our pure N-body simulation of a non-barred galaxy in Grand et al. (2012), we find that the spiral arms are transient features whose pattern speeds decrease with radius, in such a way that the pattern speed is almost equal to the rotation of star particles. We trace particle motion around the spiral arms at different radii, and demonstrate that there are star particles that are drawn towards and join the arm from behind (in front of) the arm and migrate toward the outer (inner) regions of the disc until the arm disappears as a result of their transient nature. We see this migration over the entire radial range analysed, which is a consequence of the spiral arm co-rotating at all radii. The migration is shown to largely preserve circular orbits (within a few percent). We also demonstrate that there is no significant offset of different star forming tracers across the spiral arm, which is also inconsistent with the prediction of classical density wave theory.
Cropper Mark
Grand Robert J. J.
Kawata Daisuke
No associations
LandOfFree
Dynamics of stars around spiral arms in an N-body/SPH simulated barred-spiral galaxy 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 Dynamics of stars around spiral arms in an N-body/SPH simulated barred-spiral galaxy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamics of stars around spiral arms in an N-body/SPH simulated barred-spiral galaxy will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-522887