The structure and evolution of X-ray clusters.
Abstract
Observations of the structure of the X-ray emission from 12 nearby rich clusters of galaxies are presented and interpreted in terms of dynamic cluster evolution. X-ray structures revealed by the Einstein Observatory imaging proportional counter in the range 0.25 to 3.0 keV were analyzed and used to classify the clusters based on their X-ray morphologies. Four categories are observed, consisting of spiral-rich clusters with low X-ray temperatures and velocity dispersions with broad and highly clumped emission, spiral-poor clusters with high X-ray temperatures and velocity dispersions with smoothly varying emission broadly or sharply peaked around a dominant galaxy, and clusters with emission typical of a cD galaxy in a poor cluster or group. The broad, highly clumped cluster emission is interpreted as a result of an early evolutionary stage, while the cD and centrally enhanced emissions represent successive later stages in X-ray galactic cluster evolution.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1979
- DOI:
- 10.1086/183102
- Bibcode:
- 1979ApJ...234L..21J
- Keywords:
-
- Galactic Clusters;
- Galactic Evolution;
- Galactic Structure;
- X Ray Sources;
- Emission Spectra;
- Galactic Radiation;
- Imaging Techniques;
- Proportional Counters;
- Spectrum Analysis;
- Spiral Galaxies;
- Temperature Measurement;
- Velocity Distribution;
- Astrophysics;
- Clusters of Galaxies:Evolution;
- Clusters of Galaxies:X Rays