Multiplicity of the first brightest galaxy in a cluster versus Bautz-Morgan type.
Abstract
The fraction of multiple first-brightest galaxies in Bautz-Morgan type I, I-II clusters is 7 times larger than the fraction in type III clusters. Observational evidence indicates that the 23% (28 out of 112) binary first-brightest galaxies in type I clusters are physical systems, which leads to an empirical time scale for merger of less than 4 billion yr. In contrast, the theoretical time scales for merger by dynamical friction and tidal energy exchange are approximately 30 million (or 300 million) yr.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1979
- DOI:
- 10.1086/182994
- Bibcode:
- 1979ApJ...231L...3R
- Keywords:
-
- Brightness;
- Galactic Clusters;
- Galactic Evolution;
- Statistical Analysis;
- Dynamic Characteristics;
- Energy Transfer;
- Frequency Distribution;
- Tables (Data);
- Astrophysics;
- Clusters of Galaxies:Evolution