The Halo Mass-Temperature Relation for Clusters, Groups, and Galaxies

TL;DR

This study derives and analyzes the mass-temperature relation for a diverse sample of galaxy clusters, groups, and galaxies using Chandra X-ray data, confirming theoretical predictions and assessing potential biases.

Contribution

It provides the first comprehensive M-T relation across a wide temperature range, confirming self-similar scaling and evaluating biases affecting the relation.

Findings

The M-T relation follows a power-law with slope 1.65±0.06 at R_{2500}.

The M_{200}-T relation has a slope of 1.61±0.19, consistent with the M_{2500}-T relation.

No significant evidence of slope change or break in the M-T relations.

Abstract

The halo mass-temperature relation for a sample of 216 galaxy clusters, groups, and individual galaxies observed by $Chandra$ X-ray Observatory is presented. Using accurate spectral measurements of their hot atmospheres, we derive the $M-T$ relation for systems with temperatures ranging between 0.4-15.0 keV. We measure the total mass of clusters, groups, and galaxies at radius $R_{2500}$, finding that the $M_{2500} \propto T^{\alpha}$ relation follows a power-law with $\alpha$ = 1.65$\pm$0.06. Our relation agrees with recent lensing studies of the $M-T$ relation at $R_{200}$ and is consistent with self-similar theoretical prediction and recent simulations. This agreement indicates that the $M-T$ relation is weakly affected by non-gravitational heating processes. Using lensing masses within $R_{200}$ we find $M_{200}-T$ follows a power-law with slope 1.61$\pm$0.19, consistent with the $M_{2500}-T$ relation. No evidence for a break or slope change is found in either relation. Potential biases associated with sample selection, evolution, and the assumption of hydrostatic equilibrium that may affect the scaling are examined. No significant impacts attributable to these biases are found. Non-cool-core clusters and early spirals produce higher scatter in the $M-T$ relation than cool-core clusters and elliptical galaxies.