Hidden Cooling Flows in Clusters of Galaxies II: A Wider Sample

TL;DR

This study identifies hidden cooling flows in a broader sample of galaxy clusters and elliptical galaxies, revealing significant cooling rates that impact understanding of galaxy evolution.

Contribution

It extends previous findings of hidden cooling flows to a wider, more diverse sample, demonstrating their prevalence and quantifying their cooling rates across different galaxy environments.

Findings

Hidden cooling flows detected in 6 clusters and 2 elliptical galaxies.

Cooling rates range from 1 to 40 solar masses per year in typical clusters.

Extreme clusters exhibit cooling rates of 1000 solar masses per year or more.

Abstract

We have recently uncovered Hidden Cooling Flows (HCFs) in the XMM RGS spectra of 3 clusters of galaxies, Centaurus, Perseus and A1835. Here we search for them in a wider sample of objects: the X-ray brightest group NGC5044; 4 moderate X-ray luminosity clusters Sersic 159, A262, A2052 and RXJ0821; and 3 high X-ray luminosity clusters RXJ1532, MACS 1931 and the Phoenix cluster. Finally we examine two Virgo elliptical galaxies, M49 and M84. All statistically allow the addition of an HCF. We find a significant detection of an HCF in 6 clusters and 2 elliptical galaxies. The hidden mass cooling rates are 5 to 40 Solar masses per year for the normal clusters, 1000 Solar masses per year or more for the extreme clusters and 1 to 2 Solar masses per year for the elliptical galaxies. We discuss the implications of the results for the composition of the innermost parts of the massive host galaxies and look forward to future observations.