Results 21 to 30 of about 40,302 (261)
Physics World, 2002 After a brief historical introduction, we summarize current efforts and accomplishments in the study of supermassive black holes.
Ferrarese, Laura, Merritt, David
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Unraveling the enigmatic soft x‐ray excess: Current understanding and future perspectives
Astronomische Nachrichten, Volume 344, Issue 6, August 2023., 2023 Abstract This article explores various theoretical models proposed to explain the soft x‐ray excess phenomenon, including warm Comptonization, ionized reflection models, and ionized outflowing disc winds. The soft x‐ray excess is better understood thanks to crucial observations made by ROSAT, XMM‐Newton, and eROSITA.
Thomas Boller
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Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract We are carrying out the densest and longest multiyear, multiwavelength monitoring project of OJ 287 ever done. The project MOMO (Multiwavelength Observations and Modeling of OJ 287) covers wavelengths from the radio to the high‐energy regime. A few selected observations are simultaneous with those of the Event Horizon Telescope (EHT).
S. Komossa +21 more
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Supermassive Black Holes [PDF]
Journal of High Energy Physics, Gravitation and Cosmology, 2019 In the following black hole model, electrons and positrons form a neutral gas which is confined by gravitation. The smaller masses are supported against gravity by electron degeneracy pressure. Larger masses are supported by ideal gas and radiation pressure. In each case, the gas is a polytrope which satisfies the Lane-Emden equation.
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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 rotating and twisting charged black holes with cloud of strings and quintessence
European Physical Journal C: Particles and Fields, 2023 Testing gravity theories is an important and interesting issue in relativistic astrophysics using astrophysical observations. In recent years, Event horizon telescope collaboration provided valuable data from shadow of supermassive black holes located at
Muhammad Zahid +4 more
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Searching for overlooked TDEs in the 4XMM catalogue
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract Tidal disruption events (TDEs) are usually discovered as bright transients, either in the X‐ray or optical/UV band. These events are often characterized by a “super‐soft” emission in the X‐ray band, which has not been observed in any other extragalactic source, with few exceptions (novae and supersoft active galactic nuclei, AGN), which can ...
Andrea Sacchi +2 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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A Global Inventory of Feedback
Galaxies, 2023 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 ...
Timothy M. Heckman, Philip N. Best
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Supermassive Black Holes in Bulges [PDF]
The Astrophysical Journal, 2001 26 pages, 11 Postscript figures, accepted for publication on ...
Sarzi, Marc +7 more
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