The Spatial Correlation of Bent-Tail Galaxies and Galaxy Clusters

TL;DR

This study investigates the association between bent-tail galaxies and galaxy clusters through a deep radio survey, revealing few known cluster associations and questioning existing models of bent-tail galaxy formation.

Contribution

It provides a new catalogue of bent-tail galaxies and challenges the assumption that they are predominantly found in galaxy clusters.

Findings

Only 2 of 8 bent-tail galaxies with redshifts are in known clusters.

Most bent-tail galaxies are not associated with known galaxy clusters.

Current models of bent-tail galaxies may need revision.

Abstract

We have completed a deep radio continuum survey covering 86 square degrees of the Spitzer-South Pole Telescope deep field to test whether bent-tail galaxies are associated with galaxy clusters. We present a new catalogue of 22 bent-tail galaxies and a further 24 candidate bent-tail galaxies. Surprisingly, of the 8 bent-tail galaxies with photometric redshifts, only two are associated with known clusters. While the absence of bent-tail sources in known clusters may be explained by effects such as sensitivity, the absence of known clusters associated with most bent-tail galaxies casts doubt upon current models of bent-tail galaxies.