Do the Major Axes of Rich Clusters of Galaxies Point toward Their Neighbors?
Abstract
We have used the major axis orientation of rich clusters of galaxies, determined from an analysis of X-ray images (McMillan, Kowalski, and Ulmer), to investigate whether these clusters point toward their nearest neighbors. This effect was originally reported by Binggeli for clusters whose major axes were determined from measurements of optical galaxy positions. We have analyzed Binggeli's original data. We also used updated cluster redshifts to reanalyze Binggeli's data and to combine the more recent optical work of Rhee and Katgert with our X-ray data. In no case do we find a statistically significant effect. Within the context of the cosmological models discussed by Dekel, West, and Aarseth, this result favors scenarios in which galaxies form first followed by clusters and then superclusters. Also, in cases where the X-ray image is bright and smooth, we favor use of X-ray over optical data for determining the orientation of the cluster major axis.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1989
- DOI:
- 10.1086/167228
- Bibcode:
- 1989ApJ...338..711U
- Keywords:
-
- Cosmic X Rays;
- Galactic Clusters;
- Galactic Evolution;
- Dark Matter;
- Heao 2;
- Image Analysis;
- Red Shift;
- Astrophysics;
- GALAXIES: CLUSTERING;
- GALAXIES: FORMATION;
- GALAXIES: X-RAYS