Systematic Study of Gravitational Waves from Galaxy Merger

Abstract

A systematic study of gravitational waves from galaxy mergers, through N-body simulations, was performed. In particular, we investigated the relative importance of galaxy components (disk, bulge and halo) and effects of initial relative velocity, relative angular momentum and mass ratio of the galaxies. We found that the features of light curve of gravitational waves, such as peak width and luminosity, are reliably simulated with particle numbers larger than ~10^4. Dominant contribution to gravitational wave emission came from the halo component, while peak luminosity amounted to 10^31 erg/sec for the collision of two halos with mass 3.8 x10^12Msun/h. We also found that the initial relative velocity in the direction of the initial separation did not significantly affect gravitational wave emission, while the initial relative angular momentum broadened the peak width and suppressed the luminosity. Mass dependence of the peak luminosity was also investigated, and we obtained evidence that the luminosity is proportional to the cubic mass when the scaling relation is satisfied. This behavior was considered by a simple analysis.

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Cited by in corpus (5)

• Computing General Relativistic effects from Newtonian N-body simulations: Frame dragging in the post-Friedmann approach
• Stable vortex structures in colliding self-gravitating Bose-Einstein condensates
• Revealing turbulent Dark Matter via merging of self-Gravitating condensates
• Stochastic Gravitational Wave Background originating from Halo Mergers
• Stochastic gravitational wave background from the collisions of dark matter halos