When Supermassive Black Holes Were Growing: Clues from Deep X–ray Surveys

ABSTRACT The masses of supermassive black holes at the centres of local galaxies appear to be tightly correlated with the mass and velocity dispersions of their galactic hosts. However, the local Mbh–Mstar relation inferred from dynamically measured inactive black holes is up to an order-of-magnitude higher than some estimates from active black holes, and recent work suggests that this discrepancy arises from selection bias on the sample of dynamical black hole mass measurements. In this work, we combine X-ray measurements of the mean black hole accretion luminosity as a function of stellar mass and redshift with empirical models of galaxy stellar mass growth, integrating over time to predict the evolving Mbh–Mstar relation. The implied relation is nearly independent of redshift, indicating that stellar and black hole masses grow, on average, at similar rates. Matching the de-biased local Mbh–Mstar relation requires a mean radiative efficiency ε ≳ 0.15, in line with theoretical expectations for accretion on to spinning black holes. However, matching the ‘raw’ observed relation for inactive black holes requires ε ∼ 0.02, far below theoretical expectations. This result provides independent evidence for selection bias in dynamically estimated black hole masses, a conclusion that is robust to uncertainties in bolometric corrections, obscured active black hole fractions, and kinetic accretion efficiency. For our fiducial assumptions, they favour moderate-to-rapid spins of typical supermassive black holes, to achieve ε ∼ 0.12–0.20. Our approach has similarities to the classic Soltan analysis, but by using galaxy-based data instead of integrated quantities we are able to focus on regimes where observational uncertainties are minimized.

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Accretion onto Relativistic Objects

Symposium - International Astronomical Union ◽

10.1017/s0074180900236346 ◽

1974 ◽

Vol 64 ◽

pp. 194-212

Author(s):

M. J. Rees

Keyword(s):

Black Holes ◽

Interstellar Medium ◽

Neutron Stars ◽

Binary Systems ◽

Compact Object ◽

Stellar Mass ◽

Supermassive Black Holes ◽

Compact Objects ◽

X Ray ◽

Intergalactic Space

The physics of spherically symmetrical accretion onto a compact object is briefly reviewed. Neither neutron stars nor stellar-mass black holes are likely to be readily detectable if they are isolated and accreting from the interstellar medium. Supermassive black holes in intergalactic space may however be detectable. The effects of accretion onto compact objects in binary systems are then discussed, with reference to the phenomena observed in variable X-ray sources.

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The X-Ray Halo Scaling Relations of Supermassive Black Holes

The Astrophysical Journal ◽

10.3847/1538-4357/ab3c5d ◽

2019 ◽

Vol 884 (2) ◽

pp. 169 ◽

Cited By ~ 7

Author(s):

M. Gaspari ◽

D. Eckert ◽

S. Ettori ◽

P. Tozzi ◽

L. Bassini ◽

...

Keyword(s):

Black Holes ◽

Supermassive Black Holes ◽

Scaling Relations ◽

X Ray

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The fates of merging supermassive black holes and a proposal for a new class of X-ray sources

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2581 ◽

2020 ◽

Vol 498 (3) ◽

pp. 3807-3816

Author(s):

Charles Zivancev ◽

Jeremiah Ostriker ◽

Andreas H W Küpper

Keyword(s):

Black Holes ◽

Structure Formation ◽

Hierarchical Structure ◽

Dynamical Evolution ◽

Supermassive Black Holes ◽

Host Galaxy ◽

X Ray ◽

Massive Galaxies ◽

New Class ◽

Low Mass

ABSTRACT We perform N-body simulations on some of the most massive galaxies extracted from a cosmological simulation of hierarchical structure formation with total masses in the range 1012 M⊙ < Mtot < 3 × 1013 M⊙ from 4 ≥ z ≥ 0. After galactic mergers, we track the dynamical evolution of the infalling black holes (BHs) around their host’s central BHs (CBHs). From 11 different simulations, we find that, of the 86 infalling BHs with masses >104 M⊙, 36 merge with their host’s CBH, 13 are ejected from their host galaxy, and 37 are still orbiting at z = 0. Across all galaxies, 33 BHs are kicked to a higher orbit after close interactions with the CBH binary or multiple, after which only one of them merged with their hosts. These orbiting BHs should be detectable by their anomalous (not low-mass X-ray binary) spectra. The X-ray luminosities of the orbiting massive BHs at z = 0 are in the range $10^{28}-10^{43}\, \mathrm{erg}~\mathrm{s}^{-1}$, with a currently undetectable median value of $10^{33}\, \mathrm{erg}~\mathrm{s}^{-1}$. However, the most luminous ∼5 per cent should be detectable by existing X-ray facilities.

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High Redshift Supermassive Black Holes: X-ray observations

10.1063/1.1629427 ◽

2003 ◽

Author(s):

Andrea Comastri

Keyword(s):

Black Holes ◽

High Redshift ◽

Supermassive Black Holes ◽

X Ray

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The Multiwavelength AGN Population and the X-ray Background

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314003731 ◽

2013 ◽

Vol 9 (S304) ◽

pp. 188-194

Author(s):

Ezequiel Treister ◽

Claudia M. Urry ◽

Kevin Schawinski ◽

Brooke D. Simmons ◽

Priyamvada Natarajan ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Mass Density ◽

Large Fraction ◽

Supermassive Black Holes ◽

X Rays ◽

X Ray ◽

Black Hole Growth ◽

Hole Growth ◽

X Ray Background

AbstractIn order to fully understand galaxy formation we need to know when in the cosmic history are supermassive black holes (SMBHs) growing more intensively, in what type of galaxies this growth is happening and what fraction of these sources are invisible at most wavelengths due to obscuration. Active Galactic Nuclei (AGN) population synthesis models that can explain the spectral shape and intensity of the cosmic X-ray background (CXRB) indicate that most of the SMBH growth occurs in moderate-luminosity (LX~ 1044 erg/s) sources (Seyfert-type AGN), at z~ 0.5−1 and in heavily obscured but Compton-thin, NH~ 1023cm−2, systems. However, this is not the complete history, as a large fraction of black hole growth does not emit significantly in X-rays either due to obscuration, intrinsic low luminosities or large distances. The integrated intensity at high energies indicates that a significant fraction of the total black hole growth, 22%, occurs in heavily-obscured systems that are not individually detected in even the deepest X-ray observations. We further investigate the AGN triggering mechanism as a function of bolometric luminosity, finding evidence for a strong connection between significant black hole growth events and major galaxy mergers from z~ 0 to z~ 3, while less spectacular but longer accretion episodes are most likely due to other (stochastic) processes. AGN activity triggered by major galaxies is responsible for ~60% of the total black hole growth. Finally, we constrain the total accreted mass density in supermassive black holes at z > 6, inferred via the upper limit derived from the integrated X-ray emission from a sample of photometrically selected galaxy candidates. We estimate an accreted mass density <1000 M⊙Mpc−3 at z~ 6, significantly lower than the previous predictions from some existing models of early black hole growth and earlier prior observations.

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Correlations between supermassive black holes and hot gas atmospheres in IllustrisTNG and X-ray observations

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3880 ◽

2020 ◽

Vol 501 (2) ◽

pp. 2210-2230

Author(s):

Nhut Truong ◽

Annalisa Pillepich ◽

Norbert Werner

Keyword(s):

Black Holes ◽

Supermassive Black Holes ◽

High Mass ◽

Mass Relation ◽

Host Galaxies ◽

X Ray ◽

Hierarchical Assembly ◽

Hot Gas ◽

The Masses

ABSTRACT Recent X-ray observations have revealed remarkable correlations between the masses of central supermassive black holes (SMBHs) and the X-ray properties of the hot atmospheres permeating their host galaxies, thereby indicating the crucial role of the atmospheric gas in tracing SMBH growth in the high-mass regime. We examine this topic theoretically using the IllustrisTNG cosmological simulations and provide insights to the nature of this SMBH – gaseous halo connection. By carrying out a mock X-ray analysis for a mass-selected sample of TNG100 simulated galaxies at $z$ = 0, we inspect the relationship between the masses of SMBHs and the hot gas temperatures and luminosities at various spatial and halo scales – from galactic (∼Re) to group/cluster scales (∼R500c). We find strong SMBH-X-ray correlations mostly in quenched galaxies and find that the correlations become stronger and tighter at larger radii. Critically, the X-ray temperature (kBTX) at large radii (r ≳ 5Re) traces the SMBH mass with a remarkably small scatter (∼0.2 dex). The relations emerging from IllustrisTNG are broadly consistent with those obtained from recent X-ray observations. Overall, our analysis suggests that, within the framework of IllustrisTNG, the present-time MBH–kBTX correlations at the high-mass end (MBH ≳ 108M⊙) are fundamentally a reflection of the SMBH mass–halo mass relation, which at such high masses is set by the hierarchical assembly of structures. The exact form, locus, and scatter of those scaling relations are, however, sensitive to feedback processes such as those driven by star formation and SMBH activity.

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Studying the Evolving Universe with XMM-Newton and Chandra

Symposium - International Astronomical Union ◽

10.1017/s007418090019415x ◽

2003 ◽

Vol 214 ◽

pp. 46-58 ◽

Cited By ~ 2

Author(s):

Günther Hasinger

Keyword(s):

Black Holes ◽

High Resolution ◽

Absorption Line ◽

Large Scale ◽

Cosmic Time ◽

Supermassive Black Holes ◽

Redshift Distribution ◽

X Ray ◽

X Ray Background

Two X-ray observatories, the NASA observatory Chandra and the ESA mission XMM-Newton, provide powerful new diagnostics of the “hot universe”. In this article I review recent X–ray observations of the evolving universe. First indications of the warm/hot intergalactic medium, tracing out the large scale structure of the universe, have been obtained lately in sensitive Chandra and XMM-Newton high resolution absorption line spectroscopy of bright blazars. High resolution X–ray spectroscopy and imaging also provides important new constraints on the physical condition of the cooling matter in the centers of clusters, requiring major modifications to the standard cooling flow models. One possibility is, that the supermassive black hole in the giant central galaxies significantly energizes the gas in the cluster.XMM-Newton and Chandra low resolution spectroscopy detected significant Fe Kα absorption features in the spectrum of the ultraluminous, high redshift lensed broad absorption line QSO APM 08279+5255, yielding new insights in the outflow geometry and in particular indicate a supersolar Fe/O ratio. Chandra high resolution imaging spectroscopy of the nearby ultraluminous infrared galaxy and obscured QSO NGC 6240 for the first time gave evidence of two active supermassive black holes in the same galaxy, likely bound to coalesce in the course of the ongoing major merger in this galaxy.Deep X–ray surveys have shown that the cosmic X-ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80 % of the 0.1–10 keV X-ray background into discrete sources. Optical spectroscopic identifications show that the sources producing the bulk of the X-ray background are a mixture of obscured (type–1) and unobscured (type–2) AGNs, as predicted by the XRB population synthesis models. A class of highly luminous type–2 AGN, so called QSO-2s, has been detected in the deepest Chandra and XMM-Newton surveys. The new Chandra AGN redshift distribution peaks at much lower redshifts (z ≈ 0.7) than that based on ROSAT data, indicating that the evolution of Seyfert galaxies occurs at significantly later cosmic time than that of QSOs.

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