Correlations between supermassive black holes, hot atmospheres, and the total masses of early type galaxies

K. Lakhchaura, N. Truong, N. Werner

Published 2019-04-23Version 1

We present a study of relations between the masses of the central supermassive black holes (SMBHs) and the atmospheric gas temperatures and luminosities measured within the effective radii, for a sample of 41 early-type galaxies observed by the Chandra X-ray Observatory. We report the discovery of a tight correlation between the atmospheric temperatures of the brightest cluster/group galaxies (BCGs) and their central SMBH masses, making the atmospheric gas temperature the best known proxy for SMBH masses in these systems. Furthermore, our hydrostatic analysis reveals a linear correlation between the total masses of BCGs ($M_{\rm tot}$) and their central SMBH masses ($M_{\rm BH}$). In the scenario of a simultaneous growth of central SMBHs and their host galaxies through mergers, the observed linear correlation is a natural consequence of the central limit theorem. On the other hand, quasar mode feedback would lead to a significantly steeper $M_{\rm BH}$-$M_{\rm tot}$ relation and radio mode feedback would not affect the dark matter components of the galaxies. The observed correlations between the massive dark matter dominated galaxies and their central SMBHs must thus be largely non-causal and most likely, a result of the simultaneous growth of BCGs and their SMBHs by mergers.