The Phoenix Deep Survey: Extremely Red Galaxies and Cluster Candidates

TL;DR

This study analyzes Extremely Red Galaxies in the Phoenix Deep Survey, exploring their distribution, association with faint radio sources, and identifying potential galaxy clusters, providing insights into their environments and properties.

Contribution

Introduces a new overdensity-mapping algorithm to characterize ERG distribution and identify cluster candidates, linking ERGs with faint radio sources at z > 0.5.

Findings

Tentative association between ERGs and faint radio sources at z > 0.5

Identification of several galaxy cluster candidates

Limited evidence that I - K_s > 4 selects dusty star-forming galaxies

Abstract

We present the results of a study of a sample of 375 Extremely Red Galaxies (ERGs) in the Phoenix Deep Survey, 273 of which constitute a subsample which is 80% complete to K_s = 18.5 over an area of 1160 arcmin^2. The angular correlation function for ERGs is estimated, and the association of ERGs with faint radio sources explored. We find tentative evidence that ERGs and faint radio sources are associated at z > 0.5. A new overdensity-mapping algorithm has been used to characterize the ERG distribution, and identify a number of cluster candidates, including a likely cluster containing ERGs at 0.5 < z < 1. Our algorithm is also used in an attempt to probe the environments in which faint radio sources and ERGs are associated. We find limited evidence that the I - K_s > 4 criterion is more efficient than R - K_s > 5 at selecting dusty star-forming galaxies, rather than passively evolving ERGs.