Bound Companions to Early-type Galaxies in the Core of the Coma Cluster

This project involves the study of bound companion galaxies to early-type galaxies in the core of the rich cluster of galaxies called Coma. In this project I am working with WSU astronomer Dr. Jeff Secker. The following is a brief abstract of the project and preliminary results.
A statistical analysis has been performed on a subset of the dwarf-elliptical galaxy (dE) population of the Coma galaxy cluster. The objective of this study is to determine the level at which dE galaxies exist as bound companions in the central region of the cluster. This study is based on $B$ and $R$-band CCD images of a region south of the giant galaxy NGC 4874. After modeling and subtracting the intensity profiles for ten giant galaxies, (to permit the detection of faint companions), we determined companion galaxy number densities around each of these giant galaxies, as well as nearby regions for statistical correction. These observations are complete in color and magnitude to $R$ = 22.5 mag. While a small population of bound companions is detected, the results are consistent with the majority of the dE galaxies existing freely in the general gravitational potential of the Coma cluster.

A Portion of the Coma Cluster of Galaxies Near the Center: The right side of this picture has ten giant elliptical galaxies removed. The left image is the origonal.
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