Journal articles: 'Supermassive Black Hole'

1

Ganguly, Mekhala. "M87 Supermassive Black Hole Review." International Journal of Science and Research (IJSR) 10, no. 5 (2021): 896–99. http://dx.doi.org/10.21275/sr21521182804.

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Kelly, Brandon C., and Andrea Merloni. "Mass Functions of Supermassive Black Holes across Cosmic Time." Advances in Astronomy 2012 (2012): 1–21. http://dx.doi.org/10.1155/2012/970858.

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The black hole mass function of supermassive black holes describes the evolution of the distribution of black hole mass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for constraining theoretical models of their evolution. In this paper, we discuss methods for estimating the black hole mass function, including their advantages and disadvantages. We also review the results of using these methods for estimating the mass function of both active and inactive black holes. In addition, we review current theoretical models for the growth of supermassive black holes that predict the black hole mass function. We conclude with a discussion of directions for future research which will lead to improvement in both empirical and theoretical determinations of the mass function of supermassive black holes.

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Davies, Melvyn B., Abbas Askar, and Ross P. Church. "The ecology of the galactic centre: Nuclear stellar clusters and supermassive black holes." Proceedings of the International Astronomical Union 14, S351 (2019): 80–83. http://dx.doi.org/10.1017/s1743921319006689.

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AbstractSupermassive black holes are found in most galactic nuclei. A large fraction of these nuclei also contain a nuclear stellar cluster surrounding the black hole. Here we consider the idea that the nuclear stellar cluster formed first and that the supermassive black hole grew later. In particular we consider the merger of three stellar clusters to form a nuclear stellar cluster, where some of these clusters contain a single intermediate-mass black hole (IMBH). In the cases where multiple clusters contain IMBHs, we discuss whether the black holes are likely to merge and whether such mergers are likely to result in the ejection of the merged black hole from the nuclear stellar cluster. In some cases, no supermassive black hole will form as any merger product is not retained. This is a natural pathway to explain those galactic nuclei that contain a nuclear stellar cluster but apparently lack a supermassive black hole; M33 being a nearby example. Alternatively, if an IMBH merger product is retained within the nuclear stellar cluster, it may subsequently grow, e.g. via the tidal disruption of stars, to form a supermassive black hole.

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Petri, A., A. Ferrara, and R. Salvaterra. "Supermassive black hole ancestors." Monthly Notices of the Royal Astronomical Society 422, no. 2 (2012): 1690–99. http://dx.doi.org/10.1111/j.1365-2966.2012.20743.x.

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SOHN, Bong Won. "Black Hole, Observed." Physics and High Technology 29, no. 12 (2020): 23–28. http://dx.doi.org/10.3938/phit.29.046.

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The author explains black holes in the context of astronomy and astrophysics. The history of black hole research and black hole discovery are covered briefly. The author explains why supermassive black holes in active galactic nuclei are the most promising candidates for imaging black holes. The principles of radio interferometers used as observation methods are covered. The Event Horizon Telescope Collaboration, its future plans, and the role of the Korean members are introduced.

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Jovanovic, P. "Investigation of some galactic and extragalactic gravitational phenomena." Serbian Astronomical Journal, no. 185 (2012): 1–16. http://dx.doi.org/10.2298/saj1285001j.

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Here we present a short overview of the most important results of our investigations of the following galactic and extragalactic gravitational phenomena: supermassive black holes in centers of galaxies and quasars, supermassive black hole binaries, gravitational lenses and dark matter. For the purpose of these investigations, we developed a model of a relativistic accretion disk around a supermassive black hole, based on the ray-tracing method in the Kerr metric, a model of a bright spot in an accretion disk and three different models of gravitational microlenses. All these models enabled us to study physics, spacetime geometry and effects of strong gravity in the vicinity of supermassive black holes, variability of some active galaxies and quasars, different effects in the lensed quasars with multiple images, as well as the dark matter fraction in the Universe. We also found an observational evidence for the first spectroscopically resolved sub-parsec orbit of a supermassive black hole binary system in the core of active galaxy NGC 4151. Besides, we studied applications of one potential alternative to dark matter in the form of a modified theory of gravity on Galactic scales, to explain the recently observed orbital precession of some S-stars, which are orbiting around a massive black hole at the Galactic center.

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DeGraf, Colin. "Supermassive black hole seed formation and the impact on black hole populations across cosmic time." Proceedings of the International Astronomical Union 15, S356 (2019): 292. http://dx.doi.org/10.1017/s1743921320003142.

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AbstractAlthough it is well understood that supermassive black holes are found in essentially all galaxies, the mechanisms by which they initially form remain highly uncertain, despite the importance that the formation pathway can have on AGN and quasar behaviour at all redshifts. Using a post-processing analysis method combining cosmological simulations and analytic modeling, I will discuss how varying the conditions for formation of supermassive black hole seeds leads to changes in AGN populations. Looking at formation via direct collapse or from PopIII remnants, I will discuss the impact on black hole mass and luminosity functions, scaling relations, and black hole mergers, which each have effects at both high- and low-redshifts. In addition to demonstrating the importance of initial seed formation on our understanding of long-term black hole evolution, I will also show that the signatures of seed formation suggest multiple means by which upcoming electromagnetic and GW surveys (at both high- and low-z) can provide the data required to constrain initial supermassive black hole formation.

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Jovanovic, Predrag, and Luka Popovic. "Supermassive binary black holes - possible observational effects in the x-ray emission." Facta universitatis - series: Physics, Chemistry and Technology 12, no. 2 (2014): 159–66. http://dx.doi.org/10.2298/fupct1402159j.

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Here we discuss the possible observational effects in the X-ray emission from two relativistic accretion disks in a supermassive binary black hole system. For that purpose we developed a model and performed numerical simulations of the X-ray radiation from a relativistic accretion disk around a supermassive black hole, based on the ray-tracing method in the Kerr metric, and applied it to the case of the close binary supermassive black holes. Our results indicate that the broad Fe K? line is a powerful tool for detecting such systems and studying their properties. The most favorable candidates for observational studies are the supermassive binary black holes in the galactic mergers during the phase when the orbital velocities of their components are very large and exceed several thousand kms -1.

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Chary, Ranga-Ram. "The spins of supermassive black holes." Proceedings of the International Astronomical Union 15, S356 (2019): 255. http://dx.doi.org/10.1017/s1743921320003051.

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AbstractWe present 1-second cadence, precise optical observations from SOFIA and Palomar of a sample of nearby supermassive black holes. The observations were taken to identify the shortest timescale variability in the nuclear photometry which may be associated with instabilities in the accretion flow in the immediate vicinity of the black hole. The shortest timescale variability, if associated with the radius of the innermost stable circular orbit (ISCO), can then be used to estimate the spin of the black hole. Despite 1% precision photometry, we obtained a non-detection of any significant variability in the nucleus of M32 (Mbh ∼ 2.5 × 106 Mȯ). Given the density of the stellar cusp, this argues for a scenario where 1000 Msun seed black holes formed from the coalescence of less massive black holes, which then accrete the gas produced by stellar interactions/winds. In more luminous systems however, we find a significant deection of variability and present hypotheses to explain the signal and thereby the origin of supermassive black holes.

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10

Dressler, Alan. "Observational Evidence for Supermassive Black Holes." Symposium - International Astronomical Union 134 (1989): 217–32. http://dx.doi.org/10.1017/s0074180900140914.

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A growing body of evidence from stellar dynamics in the nuclei of galaxies indicates that supermassive black holes of 107–109 M0 are common. The two best cases are M31 and M32, for which dark, central mass concentrations are the only straightforward interpretation. M87 continues to be a possible location of an even more massive black hole, but new observations and models by the author and D. Richstone effectively rule out the high black hole mass ∼5 × 109 M0 claimed by Sargent, Young, and collaborators. New data are available for several other nearby galaxies which also show kinematic signatures that could also be due to supermassive black holes. The Hubble Space Telescope will play the key role in strengthening these cases and eliminating, for the best examples, alternative models which do not require supermassive black holes.

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11

Ricarte, Angelo, Paul Tiede, Razieh Emami, Aditya Tamar, and Priyamvada Natarajan. "The ngEHT’s Role in Measuring Supermassive Black Hole Spins." Galaxies 11, no. 1 (2022): 6. http://dx.doi.org/10.3390/galaxies11010006.

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While supermassive black-hole masses have been cataloged across cosmic time, only a few dozen of them have robust spin measurements. By extending and improving the existing Event Horizon Telescope (EHT) array, the next-generation Event Horizon Telescope (ngEHT) will enable multifrequency, polarimetric movies on event-horizon scales, which will place new constraints on the space-time and accretion flow. By combining this information, it is anticipated that the ngEHT may be able to measure tens of supermassive black-hole masses and spins. In this white paper, we discuss existing spin measurements and many proposed techniques with which the ngEHT could potentially measure spins of target supermassive black holes. Spins measured by the ngEHT would represent a completely new sample of sources that, unlike pre-existing samples, would not be biased towards objects with high accretion rates. Such a sample would provide new insights into the accretion, feedback, and cosmic assembly of supermassive black holes.

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12

Komossa, S., J. G. Baker, and F. K. Liu. "Growth of Supermassive Black Holes, Galaxy Mergers and Supermassive Binary Black Holes." Proceedings of the International Astronomical Union 11, A29B (2015): 292–98. http://dx.doi.org/10.1017/s1743921316005378.

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AbstractThe study of galaxy mergers and supermassive binary black holes (SMBBHs) is central to our understanding of the galaxy and black hole assembly and (co-)evolution at the epoch of structure formation and throughout cosmic history. Galaxy mergers are the sites of major accretion episodes, they power quasars, grow supermassive black holes (SMBHs), and drive SMBH-host scaling relations. The coalescing SMBBHs at their centers are the loudest sources of gravitational waves (GWs) in the Universe, and the subsequent GW recoil has a variety of potential astrophysical implications which are still under exploration. Future GW astronomy will open a completely new window on structure formation and galaxy mergers, including the direct detection of coalescing SMBBHs, high-precision measurements of their masses and spins, and constraints on BH formation and evolution in the high-redshift Universe.

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Hoormann, J. K., P. Martini, T. M. Davis, et al. "C iv black hole mass measurements with the Australian Dark Energy Survey (OzDES)." Monthly Notices of the Royal Astronomical Society 487, no. 3 (2019): 3650–63. http://dx.doi.org/10.1093/mnras/stz1539.

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ABSTRACT Black hole mass measurements outside the local Universe are critically important to derive the growth of supermassive black holes over cosmic time, and to study the interplay between black hole growth and galaxy evolution. In this paper, we present two measurements of supermassive black hole masses from reverberation mapping (RM) of the broad C iv emission line. These measurements are based on multiyear photometry and spectroscopy from the Dark Energy Survey Supernova Program (DES-SN) and the Australian Dark Energy Survey (OzDES), which together constitute the OzDES RM Program. The observed reverberation lag between the DES continuum photometry and the OzDES emission line fluxes is measured to be $358^{+126}_{-123}$ and $343^{+58}_{-84}$ d for two quasars at redshifts of 1.905 and 2.593, respectively. The corresponding masses of the two supermassive black holes are 4.4 × 109 and 3.3 × 109 M⊙, which are among the highest redshift and highest mass black holes measured to date with RM studies. We use these new measurements to better determine the C iv radius−luminosity relationship for high-luminosity quasars, which is fundamental to many quasar black hole mass estimates and demographic studies.

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14

Lawrence, Andy. "Supermassive black hole in M87." Physics World 7, no. 7 (1994): 26. http://dx.doi.org/10.1088/2058-7058/7/7/26.

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15

Smith, Keith M. "A supermassive black hole awakes." Science 355, no. 6327 (2017): 809.4–810. http://dx.doi.org/10.1126/science.355.6327.809-d.

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Gergely, L. Á., and P. L. Biermann. "Supermassive binary black hole mergers." Journal of Physics: Conference Series 122 (July 1, 2008): 012040. http://dx.doi.org/10.1088/1742-6596/122/1/012040.

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17

Mikhailov, Alexander. "Determination of supermassive black hole spins in active galactic nuclei." Acta Astrophysica Taurica 3, no. 1 (2022): 44–47. http://dx.doi.org/10.31059/aat.vol3.iss1.pp44-47.

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Abstract Black hole spin is a key to the relativistic jet generation. Existing models are based on the Blandford–Znajek and/or Blandford–Payne mechanisms. The jet power in these models is determined by the spin value, black hole mass, magnetic fields at the event horizon, and the accretion disc. Independent estimates of mass, jet power, and magnetic field give opportunity to constrain the supermassive black hole spin value. We present an application of this approach for supermassive black holes in different samples of active galactic nuclei (AGNs). We found that the assumption about equipartition between magnetic field energy density and accreting matter energy density is reasonable for the systems with thin accretion discs. The “mass-spin” diagrams were constructed for the samples of PG quasars and distant quasars at redshift z ≈ 4.8 and demonstrated the flattening region at masses MBH ≈ 108.5M☉. These diagrams can be used to study accretion onto supermassive black holes.

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Richstone, Douglas. "11.1. Black holes and galaxy centers." Symposium - International Astronomical Union 184 (1998): 451–58. http://dx.doi.org/10.1017/s0074180900085557.

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The study of supermassive galactic black holes (BH) has moved beyond discovery to maturity. The are now ∼ 15 reliable detections. The mass of a central black hole apparently correlates with the mass of the hot component of its galactic host. It may be that every normal galaxy has a supermassive black hole carrying about 10−3 of its bulge mass, with important consequences for the structure and evolution of the core of the galaxy. The most recent major review is by Kormendy & Richstone (1995, KR).

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FILLOUX, C., F. DURIER, J. A. F. PACHECO, and J. SILK. "EVOLUTION OF SUPERMASSIVE BLACK HOLES FROM COSMOLOGICAL SIMULATIONS." International Journal of Modern Physics D 19, no. 08n10 (2010): 1233–40. http://dx.doi.org/10.1142/s0218271810017603.

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The correlations between the mass of supermassive black holes and the properties of their host galaxies are investigated through cosmological simulations. Black holes grow from seeds of 100 M⊙ are inserted into density peaks presented in the redshift range 12–15. Seeds grow essentially by accreting matter from a nuclear disk and also by coalescences resulting from merger episodes. At z = 0, our simulations reproduce the black hole mass function and the correlations of the black hole mass, both with stellar velocity dispersion and host dark halo mass. Moreover, the evolution of the black hole mass density derived from the present simulations agrees with that derived from the bolometric luminosity of quasars, indicating that the average accretion history of seeds is adequately reproduced. However, our simulations are unable to form black holes with masses above 109 M⊙ at z ~ 6, whose existence is inferred from the bright quasars detected by the Sloan survey in this redshift range.

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ROMERO, GUSTAVO E., DANIELA PÉREZ, and GABRIELA S. VILA. "SUPERMASSIVE BLACK HOLE BINARIES AT HIGH ENERGIES." International Journal of Modern Physics: Conference Series 28 (January 2014): 1460183. http://dx.doi.org/10.1142/s2010194514601835.

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An accretion disk around a supermassive black hole may be strongly perturbed by the presence of a secondary black hole. Recent simulations have shown that, under certain conditions, the tidal torques exerted by the secondary black hole may open an annular gap in the disk. In this regime, matter "overflows" across the secondary's orbit to accrete onto the primary and may feed a pair of relativistic jets. In this work we study the radiative properties of a binary system of supermassive black holes, assuming that a relativistic jet is launched from the primary and the migration of the secondary across the disk proceeds in the "overflowing" regime. The modified radiative spectrum of the disk is calculated accounting for strong gravitational effects in the innermost region. The jet emits non-thermal radiation all along the electromagnetic spectrum by interaction of locally accelerated electrons with the jet's magnetic field and internal and external radiation. In particular, we investigate whether the interaction of the relativistic electrons with the photons emitted by the accretion disk induces any signature in the spectral energy distribution of the jet that may reveal the presence of the secondary black hole.

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Green, Richard F. "AGN and the Demographics of Supermassive Black Holes." International Astronomical Union Colloquium 184 (2002): 335–42. http://dx.doi.org/10.1017/s0252921100030980.

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AbstractHigh angular resolution observations from WFPC and STIS now allow well-constrained dynamical measurement of the masses of supermassive black holes (SMBH) in nearby galaxies. An initial statistical analysis by Magorrian et al. showed that 97% of bulges host SMBH. Black hole mass is correlated moderately with bulge luminosity and strongly with the velocity dispersion of the whole bulge, suggesting that black hole formation may be an intrinsic aspect of bulge formation. Black hole masses for AGN determined from reverberation mapping fall on the same relationship with bulge velocity dispersion as those determined from stellar dynamical measurements. The prospect is therefore that the large-scale distribution of black hole masses in distant quasars may be determined through relatively straightforward measurement. Integral constraints show consistency between the total AGN luminosity density and the total volume density in SMBH contained in galaxy bulges. The strong peak of the high-luminosity quasar luminosity function at early cosmic time is consistent with the association of the build-up of SMBH through accretion and bulge formation. Alternate scenarios requiring substantial build-up of the most massive black holes at later cosmic times are more difficult to reconcile with the evolution of the LF.

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Cerruti, Matteo. "Leptonic and Hadronic Radiative Processes in Supermassive-Black-Hole Jets." Galaxies 8, no. 4 (2020): 72. http://dx.doi.org/10.3390/galaxies8040072.

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Supermassive black holes lying in the center of galaxies can launch relativistic jets of plasma along their polar axis. The physics of black-hole jets is a very active research topic in astrophysics, owing to the fact that many questions remain open on the physical mechanisms of jet launching, of particle acceleration in the jet, and on the radiative processes. In this work I focus on the last item, and present a review of the current understanding of radiative emission processes in supermassive-black-hole jets.

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Cunha, Pedro, Carlos Herdeiro, and Eugen Radu. "EHT Constraint on the Ultralight Scalar Hair of the M87 Supermassive Black Hole." Universe 5, no. 12 (2019): 220. http://dx.doi.org/10.3390/universe5120220.

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Hypothetical ultralight bosonic fields will spontaneously form macroscopic bosonic halos around Kerr black holes, via superradiance, transferring part of the mass and angular momentum of the black hole into the halo. Such a process, however, is only efficient if resonant—when the Compton wavelength of the field approximately matches the gravitational scale of the black hole. For a complex-valued field, the process can form a stationary, bosonic field black hole equilibrium state—a black hole with synchronised hair. For sufficiently massive black holes, such as the one at the centre of the M87 supergiant elliptic galaxy, the hairy black hole can be robust against its own superradiant instabilities, within a Hubble time. Studying the shadows of such scalar hairy black holes, we constrain the amount of hair which is compatible with the Event Horizon Telescope (EHT) observations of the M87 supermassive black hole, assuming the hair is a condensate of ultralight scalar particles of mass μ ∼ 10 − 20 eV, as to be dynamically viable. We show the EHT observations set a weak constraint, in the sense that typical hairy black holes that could develop their hair dynamically, are compatible with the observations, when taking into account the EHT error bars and the black hole mass/distance uncertainty.

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Gater, Will. "Milky Way black hole revealed at last." Physics World 35, no. 6 (2022): 4i. http://dx.doi.org/10.1088/2058-7058/35/06/05.

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The first picture of the glowing surroundings around Sagittarius A* – the black hole at the centre of the Milky Way – could offer clues to the inner workings of supermassive black holes. Will Gater explains.

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Narzilloev, Bakhtiyor, and Bobomurat Ahmedov. "Observational and Energetic Properties of Astrophysical and Galactic Black Holes." Symmetry 15, no. 2 (2023): 293. http://dx.doi.org/10.3390/sym15020293.

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The work reviews the investigation of electromagnetic, optical, and energetic properties of astrophysical and galactic black holes and surrounding matter. The astrophysical applications of the theoretical models of black hole environment to the description of various observed phenomena, such as cosmic rays of the ultra-high-energy, black hole shadow, gravitational lensing, quasinormal modes, jets showing relativistic effects such as the Doppler beaming, thermal radiation from the accretion discs, quasiperiodic oscillations are discussed. It has been demonstrated that the observational data strongly depends on the structure and evolution of the accretion disk surrounding the central black hole. It has been shown that the simulated images of supermassive black holes obtained are in agreement with the observational images obtained by event horizon telescope collaboration. High energetic activity from supermassive black holes due to the magnetic Penrose process discussed in the work is in agreement with the highly energetic cosmic rays observed. The astronomical observation of black holes provides rich fundamental physics laboratories for experimental tests and verification of various models of black hole accretion and different theories of gravity in the regime of strong gravity.

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Hao, Wei, Rainer Spurzem, Thorsten Naab, et al. "Resonant motions of supermassive black hole triples." Proceedings of the International Astronomical Union 10, S312 (2014): 101–4. http://dx.doi.org/10.1017/s1743921315007619.

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AbstractTriple supermassive black holes (SMBH) can form during the hierarchical mergers of massive galaxies with an existing binary. Perturbations by a third black hole may accelerate the merging process of an inner binary, for example through the Kozai mechanism. We analyze the evolution of simulated hierarchical triple SMBHs in galactic centers, and find resonances in the evolution of the semi-major axis, the eccentricity and the inclination, for both the inner and the outer orbits of the triple system, which are not only Kozai like. Through resonant oscillations, SMBH can trigger a significant increase of the inner SMBH binary eccentricity shortening the merger timescale expected from gravitational wave (GW) emission. As hierarchical triple SMBHs may be frequent in massive galaxies, the influence of orbital resonances is of great importance to our understanding of black hole coalescence and gravitational wave detection. Although Kozai mechanism is believed to play an important role in this process, detailed studies on the pattern of these resonances is necessary.

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Afrin, Misba, and Sushant G. Ghosh. "Testing Horndeski Gravity from EHT Observational Results for Rotating Black Holes." Astrophysical Journal 932, no. 1 (2022): 51. http://dx.doi.org/10.3847/1538-4357/ac6dda.

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Abstract The Event Horizon Telescope (EHT) collaboration recently unveiled the first image of the supermassive black hole M87*, which exhibited a ring of angular diameter θ d = 42 ± 3 μas, a circularity deviation of ΔC ≤ 0.1, and also inferred a black hole mass of M = (6.5 ± 0.7) × 109 M ⊙. This provides a new window onto tests of theories of gravity in the strong-field regime, including probes of violations of the no-hair theorem. It is widely believed that the Kerr metric describes astrophysical black holes, as encapsulated in the critical but untested no-hair theorem. Modeling Horndeski gravity black holes—with an additional hair parameter h besides the mass M and spin a of the Kerr black hole—as the supermassive black hole M87*, we observe that to be a viable astrophysical black hole candidate, the EHT result constrains the (a, h) parameter space. However, a systematic bias analysis indicates that rotating Horndeski black hole shadows may or may not capture Kerr black hole shadows, depending on the parameter values; the latter is the case over a substantial part of the constrained parameter space, allowing Horndeski gravity and general relativity to be distinguishable in the said space, and opening up the possibility of potential modifications to the Kerr metric.

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Schulze, Andreas, and Lutz Wisotzki. "An Estimate of the Local Active Black Hole Mass Function and the Distribution Function of Eddington Ratios." Proceedings of the International Astronomical Union 5, S267 (2009): 266. http://dx.doi.org/10.1017/s1743921310006435.

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The observed relations between the black hole mass and the properties of the spheroidal galaxy component imply a close connection between the growth of supermassive black holes and the evolution of their host galaxies. An effective approach to study black hole growth is to measure black hole masses and Eddington ratios of well-defined type 1 AGN samples and determine the underlying distribution functions.

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Hopkins, Philip F. "A black hole fundamental plane." Proceedings of the International Astronomical Union 3, S245 (2007): 219–22. http://dx.doi.org/10.1017/s1743921308017699.

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AbstractWe study observed correlations between supermassive black hole (BHs) and the properties of their host galaxies, and show that the observations define a BH “fundamental plane” (BHFP), of the form $\mbh\propto\sigma^{3.0\pm0.3}\,\re^{0.43\pm0.19}$ or $\mbh\propto\mstar^{0.54\pm0.17}\,\sigma^{2.2\pm0.5}$, analogous to the FP of elliptical galaxies. The BHFP is preferred over a simple relation between MBH and any of σ, M*, Mdyn, or Re alone at > 3 σ (99.9%) significance. The existence of this BHFP has important implications for the formation of supermassive BHs and the masses of the very largest black holes, and immediately resolves several apparent conflicts between the BH masses expected and measured for outliers in both the MBH − σ and MBH − M* relations.

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Han, Wen-Biao, Xing-Yu Zhong, Xian Chen, and Shuo Xin. "Very extreme mass-ratio bursts in the Galaxy and neighbouring galaxies in relation to space-borne detectors." Monthly Notices of the Royal Astronomical Society: Letters 498, no. 1 (2020): L61—L65. http://dx.doi.org/10.1093/mnrasl/slaa115.

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ABSTRACT Two recent papers (by Amaro-Seoane andGourgoulhon and co-workers) revealed that in our Galaxy there are very extreme mass-ratio inspirals composed of brown dwarfs and a supermassive black hole at the centre of the Galaxy. The event rates estimated in these papers are very considerable for future space-borne detectors. In addition, there are plunge events during the formation of inspiralling orbits. In this work, we calculate the gravitational waves from compact objects (brown dwarfs, primordial black holes, etc.) plunging into or being scattered by the central supermassive black hole. We find that for space-borne detectors the signal-to-noise ratios of these bursts are quite high. The event rates are estimated as ∼ 0.01 yr–1 for the Galaxy. If we are lucky, this kind of very extreme mass-ratio burst will offer a unique chance to reveal the nearest supermassive black hole and nuclei dynamics. The event rate could be as large as 4∼8 yr–1 within 10 Mpc, and because the signal is strong enough for observations by space-borne detectors, we have a good chance of being able to probe the nature of neighbouring black holes.

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FAN, JUN-HUI, YU-HAI YUAN, JIANG-SHUI ZHANG, and JIANG-HE YANG. "SUPERMASSIVE BLACK HOLE MASSES FOR BLAZARS." International Journal of Modern Physics D 17, no. 07 (2008): 1087–93. http://dx.doi.org/10.1142/s0218271808012711.

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In this work, we determine the central black hole mass for a sample of blazars including 30 γ-ray loud blazars with available variability timescales. The γ-ray energy, the emission size and the property of a two-temperature accretion disk are used to determine the absorption depth. If we take the intrinsic γ-ray luminosity to be λ times the Eddington luminosity, i.e. [Formula: see text], then we have following results: the masses of the black hole are in the range of 0.59 ~ 67.99 × 107M⊙(λ = 1.0) or 0.90 ~ 104.13 × 107M⊙(λ = 0.1). Blazars are also discussed.

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Croom, Scott M., and Stephen Fine. "Quasar and Supermassive Black Hole Evolution." Proceedings of the International Astronomical Union 5, S267 (2009): 223–30. http://dx.doi.org/10.1017/s1743921310006320.

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AbstractWe present results from statistical analysis of the largest quasar surveys currently in existence: the Sloan Digital Sky Survey (SDSS), the 2dF QSO Redshift Survey (2QZ), and the 2dF-SDSS LRG and QSO (2SLAQ) Survey. The quasar luminosity function shows highly significant (>99.9%) evidence of downsizing: the number density of faint quasars peaks at lower redshift than bright quasars. We measure the distribution of quasar broad-line widths as a function of luminosity, particularly focusing on the Mg ii λ2799 line. There is a clear trend, such that more luminous quasars show less scatter in line width than fainter quasars. However, the scatter in line width for any given luminosity (particularly in the brightest objects) is so small that it challenges our current understanding of virial black hole mass estimates.

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Crane, Leah. "Supermassive black hole was kicked out." New Scientist 234, no. 3119 (2017): 10. http://dx.doi.org/10.1016/s0262-4079(17)30604-8.

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King, Andrew. "The Supermassive Black Hole—Galaxy Connection." Space Science Reviews 183, no. 1-4 (2013): 427–51. http://dx.doi.org/10.1007/s11214-013-0018-2.

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Condon, J. J., Jeremy Darling, Y. Y. Kovalev, and L. Petrov. "A NEARLY NAKED SUPERMASSIVE BLACK HOLE." Astrophysical Journal 834, no. 2 (2017): 184. http://dx.doi.org/10.3847/1538-4357/834/2/184.

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Merritt, D. "No Supermassive Black Hole in M33?" Science 293, no. 5532 (2001): 1116–18. http://dx.doi.org/10.1126/science.1063896.

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Jones, C., and W. Forman. "The effects of outbursts from Supermassive Black Holes: A close look at M87." Proceedings of the International Astronomical Union 15, S359 (2020): 99–107. http://dx.doi.org/10.1017/s174392132000407x.

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AbstractSupermassive black holes (SMBHs) play[-105pt]Kindly check and confirm the Article Title. fundamental roles in the evolution of galaxies, groups, and clusters. The fossil record of supermassive black hole outbursts is seen through the cavities and shocks that are imprinted on these gas-rich systems. For M87, the central galaxy in the Virgo cluster, deep Chandra observations illustrate the physics of AGN feedback in hot, gas-rich atmospheres and allow measurements of the age, duration, and power of the outburst from the supermassive black hole in M87 that produced the observed cavities and shocks in the hot X-ray atmosphere.

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Boshkayev, K., A. Idrissov, O. Luongo, and D. Malafarina. "Accretion disc luminosity for black holes surrounded by dark matter." Monthly Notices of the Royal Astronomical Society 496, no. 2 (2020): 1115–23. http://dx.doi.org/10.1093/mnras/staa1564.

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ABSTRACT We consider the observational properties of a static black hole space–time immersed in a dark matter envelope. We investigate how the modifications to geometry induced by the presence of dark matter affect the luminosity of the black hole’s accretion disc. We show that the same disc luminosity as produced by a black hole in vacuum may be produced by a smaller black hole surrounded by dark matter under certain conditions. In particular, we demonstrate that the luminosity of the disc is markedly altered by the presence of dark matter, suggesting that the mass estimation of distant supermassive black holes may be changed if they are immersed in dark matter. We argue that a similar effect holds in more realistic scenarios, and we discuss the refractive index related to dark matter lensing. Finally, we show how the results presented here may help to explain the observed luminosity of supermassive black holes in the early Universe.

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DeGraf, C., and D. Sijacki. "Cosmological simulations of massive black hole seeds: predictions for next-generation electromagnetic and gravitational wave observations." Monthly Notices of the Royal Astronomical Society 491, no. 4 (2019): 4973–92. http://dx.doi.org/10.1093/mnras/stz3309.

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ABSTRACT We study how statistical properties of supermassive black holes depend on the frequency and conditions for massive seed formation in cosmological simulations of structure formation. We develop a novel method to recalculate detailed growth histories and merger trees of black holes within the framework of the Illustris simulation for several seed formation models, including a physically motivated model where black hole seeds only form in progenitor galaxies that conform to the conditions for direct collapse black hole formation. While all seed models considered here are in a broad agreement with present observational constraints on black hole populations from optical, UV, and X-ray studies, we find that they lead to widely different black hole number densities and halo occupation fractions, which are currently observationally unconstrained. In terms of future electromagnetic spectrum observations, the faint-end quasar luminosity function and the low-mass-end black hole–host galaxy scaling relations are very sensitive to the specific massive seed prescription. Specifically, the direct collapse model exhibits a seeding efficiency that decreases rapidly with cosmic time and produces much fewer black holes in low-mass galaxies, in contrast to the original Illustris simulation. We further find that the total black hole merger rate varies by more than one order of magnitude for different seed models, with the redshift evolution of the chirp mass changing as well. Supermassive black hole merger detections with LISA and International Pulsar Timing Array may hence provide the most direct means of constraining massive black hole seed formation in the early Universe.

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Zakharov, Alexander. "Supermassive black hole at the galactic center." Facta universitatis - series: Physics, Chemistry and Technology 12, no. 2 (2014): 201–10. http://dx.doi.org/10.2298/fupct1402201z.

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We derive an analytical expression of a shadow size as a function of a charge in the Reissner - Nordstr?m (RN) metric. Using the derived expression we consider shadows for negative tidal charges and charges corresponding to naked singularities q=Q2/M2>1, where Q and M are black hole charge and mass, respectively. An introduction of a negative tidal charge q can describes black hole solutions in theories with extra dimensions, so following the approach we consider an opportunity to extend RN metric to negative Q2, while for the standard RN metric Q2 is always non-negative. We found that for q > 9=8 black hole shadows disappear. Significant tidal charges q=-6.4 are not consistent with observations of a minimal spot size at the Galactic Center observed in mm-band, moreover, these observations demonstrate that in comparison with the Schwarzschild black hole a Reissner-Nordstr?m black hole with a significant charge q ? 1 provides a better fit of recent observational data for the black hole at the Galactic Center.

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Heckman, Timothy M., and Philip N. Best. "A Global Inventory of Feedback." Galaxies 11, no. 1 (2023): 21. http://dx.doi.org/10.3390/galaxies11010021.

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Feedback from both supermassive black holes and massive stars plays a fundamental role in the evolution of galaxies and the inter-galactic medium. In this paper, we use available data to estimate the total amount of kinetic energy and momentum created per co-moving volume element over the history of the universe from three sources: massive stars and supernovae, radiation pressure and winds driven by supermassive black holes, and radio jets driven by supermassive black holes. Kinetic energy and momentum injection from jets peaks at z ≈ 1, while the other two sources peak at z ≈ 2. Massive stars are the dominant global source of momentum injection. For supermassive black holes, we find that the amount of kinetic energy from jets is about an order-of-magnitude larger than that from winds. We also find that the amount of kinetic energy created by massive stars is about 2.5 εstar times that carried by jets (where εstar is the fraction of injected energy not lost to radiative cooling). We discuss the implications of these results for the evolution of galaxies and IGM. Because the ratio of the black hole mass to galaxy mass is a steeply increasing function of mass, we show that the relative importance of black hole feedback to stellar feedback likewise increases with mass. We show that there is a trend in the present-day universe which, in the simplest picture, is consistent with galaxies that have been dominated by black hole feedback being generally quenched, while galaxies that have been dominated by stellar feedback are star-forming. We also note that the amount of kinetic energy carried by jets and winds appears to be sufficient to explain the properties of hot gas in massive halos (>1013 Mʘ).

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Brenneman, Laura. "MEASURING SUPERMASSIVE BLACK HOLE SPINS IN AGN." Acta Polytechnica 53, A (2013): 652–58. http://dx.doi.org/10.14311/ap.2013.53.0652.

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Measuring the spins of supermassive black holes (SMBHs) in active galactic nuclei (AGN) can inform us about the relative role of gas accretion vs. mergers in recent epochs of the life of the host galaxy and its AGN. Recent theoretical and observation advances have enabled spin measurements for ten SMBHs thus far, but this science is still very much in its infancy. Herein, I discuss how we measure black hole spin in AGN, using recent results from a long Suzaku campaign on NGC 3783 to illustrate this process and its caveats. I then present our current knowledge of the distribution of SMBH spins in the local universe. I also address prospects for improving the accuracy, precision and quantity of these spin constraints in the next decade and beyond with instruments such as NuSTAR, Astro-H and future large-area X-ray telescopes.

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Pesce, Dominic W., Daniel C. M. Palumbo, Angelo Ricarte, et al. "Expectations for Horizon-Scale Supermassive Black Hole Population Studies with the ngEHT." Galaxies 10, no. 6 (2022): 109. http://dx.doi.org/10.3390/galaxies10060109.

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We present estimates for the number of supermassive black holes (SMBHs) for which the next-generation Event Horizon Telescope (ngEHT) can identify the black hole “shadow”, along with estimates for how many black hole masses and spins the ngEHT can expect to constrain using measurements of horizon-resolved emission structure. Building on prior theoretical studies of SMBH accretion flows and analyses carried out by the Event Horizon Telescope (EHT) collaboration, we construct a simple geometric model for the polarized emission structure around a black hole, and we associate parameters of this model with the three physical quantities of interest. We generate a large number of realistic synthetic ngEHT datasets across different assumed source sizes and flux densities, and we estimate the precision with which our defined proxies for physical parameters could be measured from these datasets. Under April weather conditions and using an observing frequency of 230 GHz, we predict that a “Phase 1” ngEHT can potentially measure ∼50 black hole masses, ∼30 black hole spins, and ∼7 black hole shadows across the entire sky.

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Rees, Martin J., and Marta Volonteri. "Massive black holes: formation and evolution." Proceedings of the International Astronomical Union 2, S238 (2006): 51–58. http://dx.doi.org/10.1017/s1743921307004681.

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AbstractSupermassive black holes are nowadays believed to reside in most local galaxies. Observations have revealed us vast information on the population of local and distant black holes, but the detailed physical properties of these dark massive objects are still to be proven. Accretion of gas and black hole mergers play a fundamental role in determining the two parameters defining a black hole: mass and spin. We briefly review here the basic properties of the population of supermassive black holes, focusing on the still mysterious formation of the first massive black holes, and their evolution from early times to now.

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Dokuchaev, Vyacheslav I., and Natalia O. Nazarova. "The Brightest Point in Accretion Disk and Black Hole Spin: Implication to the Image of Black Hole M87*." Universe 5, no. 8 (2019): 183. http://dx.doi.org/10.3390/universe5080183.

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We propose the simple new method for extracting the value of the black hole spin from the direct high-resolution image of black hole by using a thin accretion disk model. In this model, the observed dark region on the first image of the supermassive black hole in the galaxy M87, obtained by the Event Horizon Telescope, is a silhouette of the black hole event horizon. The outline of this silhouette is the equator of the event horizon sphere. The dark silhouette of the black hole event horizon is placed within the expected position of the black hole shadow, which is not revealed on the first image. We calculated numerically the relation between the observed position of the black hole silhouette and the brightest point in the thin accretion disk, depending on the black hole spin. From this relation, we derive the spin of the supermassive black hole M87*, a = 0.75 ± 0.15 .

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Gais, Joseph, Adrian Ka-Wai Chung, Mark Ho-Yeuk Cheung, and Tjonnie G. F. Li. "Finding the Ultralight Boson from a Black Hole’s Ringdown." Journal of Physics: Conference Series 2156, no. 1 (2021): 012078. http://dx.doi.org/10.1088/1742-6596/2156/1/012078.

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Abstract Solving the problem of dark matter remains one of the greatest unsolved mystery of fundamental physics. One possible dark matter candidate is the scalar ultralight boson, with mass « 1eV. If they exist, ultralight bosons will form clouds of significant total mass about rotating black holes, affecting the spacetime around the black hole. After the inspiral phase of a binary merger, the bosonic cloud can affect the perturbations to the black hole, resulting in deviations in the quasinormal mode frequencies of the ringdown signal of a binary merger. Here, we compute these shifts in the gravitational quasinormal mode frequencies for such a system, and conduct an injection campaign with supermassive black holes detected by the Laser Interferometer Space Antenna. We find that detections of the ringdown phase of supermassive black holes can rule out or confirm the existence of cloud-forming ultralight bosons of mass ∼ 10−18eV at redshift z > 1 if cloud dissipation effects during the inspiral can be neglected.

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De Laurentis, Mariafelicia, and Paolo Salucci. "The Accurate Mass Distribution of M87, the Giant Galaxy with Imaged Shadow of Its Supermassive Black Hole, as a Portal to New Physics." Astrophysical Journal 929, no. 1 (2022): 17. http://dx.doi.org/10.3847/1538-4357/ac54b9.

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Abstract The very careful Event Horizon Telescope estimate of the mass of the supermassive black hole at the center of the giant cD galaxy M87, allied with recent high-quality photometric and spectroscopic measurements, yields a proper dark/luminous mass decomposition from the galaxy center to its virial radius. That provides us with decisive information on crucial cosmological and astrophysical issues. The dark and the standard matter distributions in a wide first time detected galaxy region under the supermassive black hole gravitational control. The well-known supermassive black hole mass versus stellar dispersion velocity relationship at the highest galaxy masses implies an exotic growth of the former. This may be the first case in which one can argue that the supermassive black hole mass growth was also contributed by the dark matter component. A huge dark matter halo core in a galaxy with inefficient baryonic feedback is present and consequently constrains the nature of the dark halo particles. The unexplained entanglement between dark/luminous structural properties, already emerged in disk systems, also appears.

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Shields, Joseph C., Carl Jakob Walcher, Torsten Böker, Luis C. Ho, Hans-Walter Rix, and Roeland P. van der Marel. "An accreting black hole in the nucleus of the bulgeless galaxy NGC 1042." Proceedings of the International Astronomical Union 3, S245 (2007): 259–60. http://dx.doi.org/10.1017/s1743921308017869.

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AbstractCompact star clusters are commonly found in the centers of galaxies and may foster formation of intermediate-mass “seed” black holes that facilitate the growth of supermassive black holes in galaxy nuclei. Such star clusters can be studied with minimal background starlight contamination in bulgeless galaxies. We present new results that point to the presence of an accreting black hole associated with the central star cluster in the Sd galaxy NGC 1042, and discuss implications for the bulge-black hole connection.

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Shankar, Francesco, David H. Weinberg, Christopher Marsden, et al. "Probing black hole accretion tracks, scaling relations, and radiative efficiencies from stacked X-ray active galactic nuclei." Monthly Notices of the Royal Astronomical Society 493, no. 1 (2019): 1500–1511. http://dx.doi.org/10.1093/mnras/stz3522.

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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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Graham, Alister W. "Black hole and nuclear cluster scaling relations: Mbh ∝ Mnc2.7±0.7." Proceedings of the International Astronomical Union 10, S312 (2014): 269–73. http://dx.doi.org/10.1017/s1743921315008017.

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AbstractThere is a growing array of supermassive black hole and nuclear star cluster scaling relations with their host spheroid, including a bent (black hole mass)–(host spheroid mass) Mbh–Msph relation and a different (massive compact object mass)–(host spheroid velocity dispersion) Mmco–σ relations for black holes and nuclear star clusters. By combining the observed Mbh ∝ σ5.5 relation with the observed Mnc ∝ σ1.6–2.7 relation, we derive the expression Mbh ∝ Mnc2–3.4, which should hold until the nuclear star clusters are eventually destroyed in the larger core-Sérsic spheroids. This new mass scaling relation helps better quantify the rapid evolutionary growth of massive black holes in dense star clusters, and the relation is consistently recovered when coupling the observed Mnc ∝ Msph0.6–1.0 relation with the recently observed quadratic relation Mbh ∝ Msph2 for Sérsic spheroids.

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Journal articles on the topic 'Supermassive Black Hole'

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