Relaxation and Thermalization in Spiral Galaxies Mediated by Spiral Wave Scattering

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We have constructed N-body particle-mesh simulations of disk galaxies in which the relaxation times of the simulated disks (as measured by thermalization of the disk, i.e. increase in Toomre's Q parameter) is comparable to the actual relaxation time scale in actual disk galaxies (several tens of rotation periods). These simulations require 1M to 4M particles (1M = 2(20) ), consistent with the work of White and of Comins and Schroeder on the dependence of relaxation time on N. We observe that during the interval when Q is increasing, that the Fourier power associated with spiral modes is large. When Q has risen to its asymptotic value in the simulation, the Fourier power diminishes to a low level. This suggests a scenario in which stars (simulation particles) scatter off the time-varying spiral potential, as suggested by Carlberg and Sellwood. Eventually random velocities of stars increase to a value which quenches the spiral instability. We compare the heating rates in our simulations at observed spiral wave amplitudes to the expected growth rates as given by Carlberg and Sellwood.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Relaxation and Thermalization in Spiral Galaxies Mediated by Spiral Wave Scattering 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 Relaxation and Thermalization in Spiral Galaxies Mediated by Spiral Wave Scattering, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relaxation and Thermalization in Spiral Galaxies Mediated by Spiral Wave Scattering will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-780099

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.