Near-infrared polarimetry as a tool for testing properties of accreting supermassive black holes

Supermassive black holes in the central parts of galaxies have been extensively studied after a quasar was discovered in 1963. Quasars and active galactic nuclei are known to emit large amounts of electromagnetic radiation over a wide range of wavelengths within a very small volume. These objects are suggested to harbor massive black holes because a plausible mechanism for producing energy efficiently is conversion of the deep gravitational energy of a massive and compact object right after the discovery of the quasar. Astronomers also discovered that the central part of our galaxy has a strong concentration of mass as initially inferred from the rapid motion of the ionized gas near the center. In order to investigate the nature of that concentrated mass, a German group led by Reinhard Genzel and a US group led by Andrea Ghez improved the angular resolution by adopting speckle interferometry and adaptive optics in the near infrared so that very high resolution imaging of the stars in a small region around the Galactic center became possible. Since the mid 1990s, these two groups have made precision measurements of the positions of a large number of stars in the Galactic center and obtained their trajectories accurately. The gravitational field is found to be consistent with that due to a nearly point mass of about 4 million solar masses. Together with gravitational wave observations, imaging of the black hole shadow by with the Event Horizon Telescope, we now have firm observational evidence for the existence of black holes with a huge range of masses in the universe. Another big question to be answered is how these supermassive black holes are formed.

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Probing the elliptical orbital configuration of the close binary of supermassive black holes with differential interferometry

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038733 ◽

2020 ◽

Vol 644 ◽

pp. A88

Author(s):

Andjelka B. Kovačević ◽

Yu-Yang Songsheng ◽

Jian-Min Wang ◽

Luka Č. Popović

Keyword(s):

Black Holes ◽

Near Infrared ◽

Orbital Motion ◽

Supermassive Black Holes ◽

Spectral Lines ◽

Close Binary ◽

Close Binaries ◽

Large Telescope ◽

Differential Phase ◽

Differential Interferometry

Context. Obtaining detections of electromagnetic signatures from the close binaries of supermassive black holes (CB-SMBH) is still a great observational challenge. The Very Large Telescope Interferometer (VLTI) and the Extremely Large Telescope (ELT) will serve as a robust astrophysics suite offering the opportunity to probe the structure and dynamics of CB-SMBH at a high spectral and angular resolution. Aims. Here, we explore and illustrate the application of differential interferometry on unresolved CB-SMBH systems in elliptical orbital configurations. We also investigate certain peculiarities of interferometry signals for a single SMBH with clouds in elliptical orbital motion. Methods. Photocentre displacements between each SMBH and the regions in their disc-like broad line regions (BLR) appear as small interferometric differential phase variability. To investigate the application of interferometric phases for the detection of CB-SMBH systems, we simulated a series of differential interferometry signatures, based on our model comprising ensembles of clouds surrounding each supermassive black hole in a CB-SMBH. By setting the model to the parameters of a single SMBH with elliptical cloud motion, we also calculated a series of differential interferometry observables for this case. Results. We found various deviations from the canonical S-shape of the CB-SMBH phase profile for elliptically configured CB-SMBH systems. The amplitude and specific shape of the interferometry observables depend on the orbital configurations of the CB-SMBH system. We get distinctive results when considering anti-aligned angular momenta of cloud orbits with regard to the total CB-SMBH angular momentum. We also show that their velocity distributions differ from the aligned cloud orbital motion. Some simulated spectral lines from our model closely resemble observations from the Paα line obtained from near-infrared AGN surveys. We found differences between the “zoo” of differential phases of single SMBH and CB-SMBH systems. The “zoo” of differential phases for a single SMBH take a deformed S shape. We also show how their differential phase shape, amplitude, and slope evolve with various sets of cloud orbital parameters and the observer’s position. Conclusions. We calculate an extensive atlas of the interferometric observables, revealing distinctive signatures for the elliptical configuration CB-SMBH. We also provide an interferometry atlas for the case of a single SMBH with clouds with an elliptical motion, which differs from those of a CB-SMBH. These maps can be useful for extracting exceptional features of the BLR structure from future high-resolution observations of CB-SMBH systems, but also of a single SMBH with clouds in an elliptical orbital setup.

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SUPERMASSIVE BLACK HOLES AND THEIR HOST GALAXIES. II. THE CORRELATION WITH NEAR-INFRARED LUMINOSITY REVISITED

The Astrophysical Journal ◽

10.1088/0004-637x/780/1/70 ◽

2013 ◽

Vol 780 (1) ◽

pp. 70 ◽

Cited By ~ 43

Author(s):

Ronald Läsker ◽

Laura Ferrarese ◽

Glenn van de Ven ◽

Francesco Shankar

Keyword(s):

Black Holes ◽

Near Infrared ◽

Supermassive Black Holes ◽

Host Galaxies

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Epicyclic Oscillations around Simpson–Visser Regular Black Holes and Wormholes

Universe ◽

10.3390/universe7080279 ◽

2021 ◽

Vol 7 (8) ◽

pp. 279

Author(s):

Zdeněk Stuchlík ◽

Jaroslav Vrba

Keyword(s):

Black Holes ◽

Black Hole ◽

Active Galactic Nuclei ◽

Observational Data ◽

High Frequency ◽

Galactic Nuclei ◽

Supermassive Black Holes ◽

Periodic Oscillations ◽

High Length ◽

Circular Geodesic

We study epicyclic oscillatory motion along circular geodesics of the Simpson–Visser meta-geometry describing in a unique way regular black-bounce black holes and reflection-symmetric wormholes by using a length parameter l. We give the frequencies of the orbital and epicyclic motion in a Keplerian disc with inner edge at the innermost circular geodesic located above the black hole outer horizon or on the our side of the wormhole. We use these frequencies in the epicyclic resonance version of the so-called geodesic models of high-frequency quasi-periodic oscillations (HF QPOs) observed in microquasars and around supermassive black holes in active galactic nuclei to test the ability of this meta-geometry to improve the fitting of HF QPOs observational data from the surrounding of supermassive black holes. We demonstrate that this is really possible for wormholes with sufficiently high length parameter l.

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Cosmological Evolution of Supermassive Black Holes: Mass Functions and Spins

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312019904 ◽

2012 ◽

Vol 8 (S290) ◽

pp. 259-260 ◽

Cited By ~ 1

Author(s):

Yan-Rong Li ◽

Jian-Min Wang ◽

Luis C. Ho

Keyword(s):

Black Holes ◽

Mass Function ◽

Supermassive Black Holes ◽

Cosmological Evolution ◽

Radiative Efficiency ◽

Bolometric Luminosity ◽

History Of ◽

Minor Mergers ◽

Mass Dependent ◽

Mass Functions

AbstractWe derive the mass function of supermassive black holes (SMBHs) over the redshift range 0 > z ≲ 2, using the latest deep luminosity and mass functions of field galaxies. Applying this mass function, combined with the bolometric luminosity function of active galactic nuclei (AGNs), into the the continuity equation of SMBH number density, we explicitly obtain the mass-dependent cosmological evolution of the radiative efficiency for accretion. We suggest that the accretion history of SMBHs and their spins evolve in two distinct regimes: an early phase of prolonged accretion, plausibly driven by major mergers, during which the black hole spins up, then switching to a period of random, episodic accretion, governed by minor mergers and internal secular processes, during which the hole spins down. The transition epoch depends on mass, mirroring other evidence for “cosmic downsizing” in the AGN population.

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The ecology of the galactic centre: Nuclear stellar clusters and supermassive black holes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319006689 ◽

2019 ◽

Vol 14 (S351) ◽

pp. 80-83 ◽

Cited By ~ 1

Author(s):

Melvyn B. Davies ◽

Abbas Askar ◽

Ross P. Church

Keyword(s):

Black Holes ◽

Black Hole ◽

Large Fraction ◽

Galactic Nuclei ◽

Supermassive Black Holes ◽

Galactic Centre ◽

Stellar Clusters ◽

Stellar Cluster ◽

Supermassive Black Hole ◽

Multiple Clusters

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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The radio-loud narrow-line Seyfert 1 galaxy 1H 0323+342 in a galaxy merger

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1525 ◽

2020 ◽

Vol 496 (2) ◽

pp. 1757-1765 ◽

Cited By ~ 1

Author(s):

Akihiro Doi ◽

Motoki Kino ◽

Nozomu Kawakatu ◽

Kazuhiro Hada

Keyword(s):

Black Holes ◽

Near Infrared ◽

Gamma Ray ◽

Linear Structure ◽

Seyfert Galaxies ◽

Mass Function ◽

High Mass ◽

Host Galaxy ◽

Supporting Evidence ◽

Narrow Line

ABSTRACT The supermassive black holes (SMBHs) of narrow-line Seyfert 1 galaxies (NLS1s) are at the lower end of the mass function of active galactic nuclei (AGNs) and reside preferentially in late-type host galaxies with pseudobulges, which are thought to be formed by internal secular evolution. On the other hand, the population of radio-loud NLS1s presents a challenge for the relativistic jet paradigm, which states that powerful radio jets are associated exclusively with very high mass SMBHs in elliptical hosts, which are built up through galaxy mergers. We investigated distorted radio structures associated with the nearest gamma-ray-emitting, radio-loud NLS1, 1H 0323+342. This provides supporting evidence for the merger hypothesis based on past optical/near-infrared observations of its host galaxy. The anomalous radio morphology consists of two different structures: the inner curved structure of the currently active jet and an outer linear structure of low-brightness relics. Such coexistence might be indicative of the stage of an established black hole binary with precession before the black holes coalesce in the galaxy merger process. 1H 0323+342 and other radio-loud NLS1s under galaxy interactions may be extreme objects on the evolutionary path from radio-quiet NLS1s to normal Seyfert galaxies with larger SMBHs in classical bulges through mergers and merger-induced jet phases.

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