A Study of Central Galaxy Rotation with Stellar Mass and Environment

TL;DR

This study investigates how galaxy stellar mass and environment influence the likelihood of slow rotation in central galaxies, revealing that mass increases this probability while environment factors like halo mass and cluster dominance do not have significant effects.

Contribution

It provides new integral-field observations and analysis showing that stellar mass correlates with slow galaxy rotation, challenging the idea that halo mass solely determines galaxy properties.

Findings

Higher stellar mass increases slow rotation probability.

Halo mass shows no significant effect on rotation.

Cluster dominance does not influence galaxy rotation.

Abstract

We present a pilot analysis of the influence of galaxy stellar mass and cluster environment on the probability of slow rotation in 22 central galaxies at mean redshift $z=0.07$. This includes new integral-field observations of 5 central galaxies selected from the Sloan Digital Sky Survey, observed with the SPIRAL integral-field spectrograph on the Anglo-Australian Telescope. The composite sample presented here spans a wide range of stellar masses, $10.9<$log(M$_{*}/$M$_{\odot})<12.0$, and are embedded in halos ranging from groups to clusters, $12.9<$log(M$_{200}/$M$_{\odot})<15.6$. We find a mean probability of slow rotation in our sample of P(SR)$=54\pm7$percent. Our results show an increasing probability of slow rotation in central galaxies with increasing stellar mass. However, when we examine the dependence of slow rotation on host cluster halo mass we do not see a significant relationship. We also explore the influence of cluster dominance on slow rotation in central galaxies. Clusters with low dominance are associated with dynamically younger systems. We find that cluster dominance has no significant effect on the probability of slow rotation in central galaxies. These results conflict with a paradigm in which halo mass alone predetermines central galaxy properties.