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Investigation of some galactic and extragalactic gravitational phenomena [PDF]
Serbian Astronomical Journal, 2012 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 ...
Jovanović P.
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An Upper Limit on the Charge of the Black Hole Sgr A* from EHT Observations
The Astrophysical Journal, 2023 The Event Horizon Telescope (EHT) recently released an image of the supermassive black hole Sgr A* showing an angular shadow diameter d _sh = 48.7 ± 7 μ as and Schwarzschild shadow deviation $\delta =-{0.08}_{-0.09}^{+0.09}\,(\mathrm{VLTI})$ , $-{0.04}_{-
Sushant G. Ghosh, Misba Afrin
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On the Formation and Interaction of Multiple Supermassive Stars in Cosmological Flows
The Astrophysical Journal, 2023 Supermassive primordial stars with masses exceeding ∼10 ^5 M _⊙ that form in atomically cooled halos are the leading candidates for the origin of high-redshift quasars at z > 6.
Tyrone E. Woods +3 more
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The ngEHT’s Role in Measuring Supermassive Black Hole Spins
Galaxies, 2022 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 (
Angelo Ricarte +4 more
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Energy Flux and Particle Flux in Steady-state Solutions of Nuclear Star Clusters
The Astrophysical Journal, 2023 We examine the effects of two-body interactions in a nuclear star cluster surrounding a supermassive black hole. We evaluate the energy flux, analogously to the particle flux calculation of Bahcall and Wolf.
Barak Rom, Itai Linial, Re’em Sari
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The Case for the Fundamental MBH-σ Relation
Frontiers in Physics, 2020 Strong scaling relations between host galaxy properties (such as stellar mass, bulge mass, luminosity, effective radius etc) and their nuclear supermassive black hole's mass point toward a close co-evolution.
Christopher Marsden +3 more
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Visible Shapes of Black Holes M87* and SgrA*
Universe, 2020 We review the physical origins for possible visible images of the supermassive black hole M87* in the galaxy M87 and SgrA* in the Milky Way Galaxy. The classical dark black hole shadow of the maximal size is visible in the case of luminous background ...
Vyacheslav I. Dokuchaev +1 more
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Leptonic and Hadronic Radiative Processes in Supermassive-Black-Hole Jets
Galaxies, 2020 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 ...
Matteo Cerruti
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Universe, 2019 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.
Vyacheslav I. Dokuchaev +1 more
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Shadow of a rotating squashed Kaluza-Klein black hole
Journal of High Energy Physics, 2019 We study the shadow of a rotating squashed Kaluza-Klein (KK) black hole and the shadow is found to possess distinct properties from those of usual rotating black holes.
Fen Long +3 more
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