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

Abstract

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 a range of radii between R e and 5R e , for a sample of 47 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. Furthermore, our hydrostatic analysis reveals an approximately linear correlation between the total masses of BCGs (M tot ) and their central SMBH masses (M BH ). State-of-the-art cosmological simulations show that the SMBH mass could be determined by the binding energy of the halo through radiative feedback during the rapid black hole growth by accretion, while for the most massive galaxies mergers are the chief channel of growth. In the scenario of a simultaneous growth of central SMBHs and their host galaxies through mergers, the observed linear correlation could be a natural consequence of the central limit theorem.

Feedback from Active Galactic Nuclei in Galaxy Groups

“…It has been suggested that SMBH properties are fundamentally linked with the mass of the host halo [74,75], and that the M BH − L K and M BH − σ v relations arise as a byproduct from the scaling relations between halo mass and optical galaxy properties. Several recent studies seem to confirm that the mass of the central SMBH is more tightly related to the temperature of the host gaseous halo, i.e., the global gravitational potential and hot-halo processes [76][77][78]. We discuss this point, in detail, in Section 5.3.…”

“…However, it is still unclear whether the optical scaling relations of SMBH are fundamental or derive from correlations with other key quantities. Recent findings have instead unveiled that the SMBH masses are more tightly correlated with the properties of the host X-ray gaseous halos, especially in the IGrM regime [76][77][78]. In Figure 16, we summarize our current knowledge of the relation between SMBH mass and X-ray temperature within the core of galaxy groups (R < ∼ 0.15 R 500 ).…”

X-ray signatures of black hole feedback: hot galactic atmospheres in IllustrisTNG and X-ray observations

“…Regarding the radial trends found in TNG, the analysis of the relatively small sample of BCGs from Lakhchaura et al (2019) indicates that the scatter in the MBH − TX relation (∼ 0.26 dex) does not change significantly between Re and 5Re. On the other hand, the data from Gaspari et al 2019 suggest that the MBH − TX relation at cluster core scale (∼ 0.1R500c) has larger intrinsic scatter compared to the one within a smaller galactic/CGM scale, 0.25±0.02 versus 0.21±0.03, i.e.…”

Scaling Properties of Galaxy Groups

“…Bharadwaj et al [17] also found that brightest group galaxies have a higher stellar mass than brightest cluster galaxies, suggesting that there is less gas available to feed the SMBHs. Recent results suggest that the IGrM and intracluster medium (ICM) are also providing a source of gas which feeds and grows the central SMBHs, in particular leading to novel scaling relations between the SMBH mass and the X-ray properties of their host gaseous halos (e.g., Bogdán et al [19], Gaspari et al [20], Lakhchaura et al [21]). These findings imply an interplay between the feedback mechanisms connected with the SMBHs and the macro-scale halos, which could explain some features of cosmological simulations driving a relative break of the L x -T x and L x -M relations at low temperatures (e.g., McCarthy et al [14], Sijacki et al [22], Puchwein et al [23], Fabjan et al [24], Le Brun et al [25]).…”