Simulations of galaxy mergers. II
Abstract
Mergers of elliptical galaxies are investigated by numerical simulations using a collisionless N-body code with 2400 particles. The initial galaxies are spherical and nonrotating with Hubble-type profiles and isotropic velocity distributions, having a mass ratio of 3:1 with a compact secondary. The galaxies are initiated in low energy orbits from which they merge through orbital decay. The remnants have Hubble-type density profiles and 'isothermal' haloes tend to form in some cases, while the density profiles are found to be inconsistent with de Vaucouleurs (1948) profiles. The remnants are determined to have little flattening up to E3 and they are oblate, triaxial, or prolate depending on impact parameter, while there is little velocity anisotropy. Significant rotation with solid body rotation out to the half mass radius followed by a slow decline is observed in some remnants. It is found that the central density and velocity dispersion decrease and the core radius and tidal radius increase. Although there is little radial mixing, the remains of the smaller galaxy end up in the outer parts of the remnant where they can give rise to a color gradient.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 1983
- DOI:
- 10.1093/mnras/204.1.219
- Bibcode:
- 1983MNRAS.204..219V
- Keywords:
-
- Astronomical Models;
- Elliptical Galaxies;
- Galactic Evolution;
- Galactic Structure;
- Angular Velocity;
- Computerized Simulation;
- Density Distribution;
- Many Body Problem;
- Mass Transfer;
- Astronomy