Computer Simulations of Interacting Galaxies in Compact Groups and the Observed Properties of Triple Galaxies
Abstract
Triplets of galaxies offer a good opportunity to measure the amount of dark matter in systems of galaxies. We use the extensive data set on triplets by Karachentsev et al. [Isv. Spec. Astrophys. Obs., 27, 67 (1989)], and try to model it by using computer simulations of interacting galaxies. Our simulated interactions include dynamical friction and mergers in addition to the usual, softened Newtonian potential. We start with bound five galaxy systems of various kinds. When only three galaxies remain after mergers, the systems are studied at many different projection angles in order to simulate the observed triplets. In all, nearly 10000 five galaxy systems were calculated, and each was viewed from 20 random angles in order to derive statistical properties of the simulated triplets. The following conclusions may be drawn after comparison with Karachentsev et al.'s sample: It is possible to determine the mean mass of the triplets within an accuracy of about 40%. The best estimate for the mean mass-to-light ratio in Karachentsev triplets is 50 +/- 20 in solar units. The geometry of the projected configurations of the simulated triplets and the Karachentsev et al. triplets agree very well, in contrast to earlier three-body modeling. Overall, the observed properties of Karachentsev triplets agree well with the assumption that these triplets represent temporary phases in the evolution of small groups of galaxies.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 1993
- DOI:
- 10.1086/116582
- Bibcode:
- 1993AJ....105.2047Z
- Keywords:
-
- Astronomical Models;
- Computerized Simulation;
- Galactic Clusters;
- Interacting Galaxies;
- Dark Matter;
- Galactic Evolution;
- Astrophysics;
- GALAXIES: CLUSTERING;
- DARK MATTER;
- GALAXIES: KINEMATICS AND DYNAMICS