Results 51 to 60 of about 32,361 (211)

Primordial black holes as dark matter candidates

SciPost Physics Lecture Notes, 2022
We review the formation and evaporation of primordial black holes (PBHs) and their possible contribution to dark matter. Various constraints suggest they could only provide most of it in the mass windows $10^{17}$ - $10^{23}\,$g or $10$ - $10^{2}\,M_ ...
Bernard Carr, Florian Kuhnel
doaj   +1 more source

A Radio Census of Binary Supermassive Black Holes

, 2010
Using archival VLBI data for 3114 radio-luminous active galactic nuclei, we searched for binary supermassive black holes using a radio spectral index mapping technique which targets spatially resolved, double radio-emitting nuclei.
Beasley, Begelman, Boroson, Britzen, Colpi, Comerford, De Lucia, De Propris, Decarli, Detweiler, Dunlop, Enoki, Ferrarese, Fomalont, Frank, Giovannini, Gualandris, Haring, Jaffe, Jenet, Komossa, Komossa, Kovalev, Lacey, Lister, Lovell, Mason, Mauch, McLure, Merritt, Merritt, Myers, Owsianik, Padovani, Peterson, Petrov, Petrov, Petrov, Pollack, Rajagopal, Rodriguez, S. Burke-Spolaor, Saripalli, Sault, Sesana, Sesana, Slee, Springel, Sudou, Valtonen, Volonteri, Walker, Wang, Wen, Wilkinson, Wyithe, Yu   +56 more
core   +1 more source

A Markov Chain Monte Carlo approach for measurement of jet precession in radio-loud active galactic nuclei [PDF]

, 2020
© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Jet precession can reveal the presence of binary systems of supermassive black holes.
Hardcastle, Martin J., Horton, Maya, Krause, Martin G. H., Read, Shaun C.   +3 more
core   +3 more sources

Formation of Supermassive Black Hole Seeds [PDF]

Publications of the Astronomical Society of Australia, 2016
AbstractThe detection of quasars at z > 6 unveils the presence of supermassive black holes of a few billion solar masses. The rapid formation process of these extreme objects remains a fascinating and open issue. Such discovery implies that seed black holes must have formed early on, and grown via either rapid accretion or BH/galaxy mergers. In this
Latif, M., FERRARA, ANDREA
openaire   +2 more sources

Hidden No More: Spotlight on Tidal Disruption Events in Active Galactic Nuclei

Astronomische Nachrichten, EarlyView.
ABSTRACT Tidal disruption events (TDEs) are typically discovered in previously quiescent galaxies. However, earlier studies have revealed a handful of TDEs occurring in pre‐existing active galactic nuclei (AGN). We discuss AT2019aalc, a promising TDE candidate in an AGN, and compare it to similar sources.
Patrik Milán Veres
wiley   +1 more source

Supermassive Black Hole Growth in Hierarchically Merging Nuclear Star Clusters

The Astrophysical Journal
Supermassive black holes are prevalent at the centers of massive galaxies, and their masses scale with galaxy properties, increasing evidence suggesting that these trends continue to low stellar masses.
Konstantinos Kritos, Ricarda S. Beckmann, Joseph Silk, Emanuele Berti, Sophia Yi, Marta Volonteri, Yohan Dubois, Julien Devriendt   +7 more
doaj   +1 more source

Is there life inside black holes?

, 2011
Bound inside rotating or charged black holes, there are stable periodic planetary orbits, which neither come out nor terminate at the central singularity. Stable periodic orbits inside black holes exist even for photons. These bound orbits may be defined
Balek V, Bičák J, Carter B, Chandrasekhar S, Dotti G, Frolov V P, Grunau S Kagramanova V, Kardashev N S, Landau L D, Misner C W, Novikov I D, Olivares M Saavedra J Leiva C Villanueva J R, Pugliese D Quevedo H Ruffini R, V I Dokuchaev, Wald R M, Zeldovich Ya B   +15 more
core   +1 more source

A NEARLY NAKED SUPERMASSIVE BLACK HOLE [PDF]

The Astrophysical Journal, 2017
ABSTRACT During a systematic search for supermassive black holes (SMBHs) not in galactic nuclei, we identified the compact, symmetric radio source B3 1715+425 with an emission-line galaxy offset ≈ 8.5
J. J. Condon, Jeremy Darling, Y. Y. Kovalev, L. Petrov   +3 more
openaire   +4 more sources

Axion Black Hole Solution in Non‐Metricity Gravity

Fortschritte der Physik, Volume 74, Issue 2, February 2026.
Abstract A static, spherically symmetric black hole solution in symmetric teleparallel (non‐metricity) gravity sourced by an axion field is constructed. Starting from the modified field equations, exact configurations are obtained characterized by the mass M$M$ and an axion–geometry coupling β$\beta$, with temporal metric function A(r)=1−2Mr+βr$A(r)=1-\
A. Eid, G.G.L. Nashed
wiley   +1 more source

Testing the Weak Cosmic Censorship Conjecture via Test Particle–Induced Overcharging/Overspinning of Kerr–Newman–Modified Gravity Black Hole

Advances in Astronomy, Volume 2026, Issue 1, 2026.
We examine the weak cosmic censorship conjecture (WCCC) violation by throwing a charged and rotating test particle into a Kerr–Newman–modified gravity black hole (KN–MOG BH). The result depends on several factors, such as the relative sign of the particle’s charge and its direction of rotation with respect to black hole (BH).
Waqar Ahmad, Abdul Rehman Kashif, Jose Gaite   +2 more
wiley   +1 more source