Results 11 to 20 of about 5,974 (69)
Growth of Accreting Supermassive Black Hole Seeds and Neutrino Radiation
Journal of Astrophysics, Volume 2015, Issue 1, 2015., 2015 In the framework of microscopic theory of black hole (MTBH), which explores the most important processes of rearrangement of vacuum state and spontaneous breaking of gravitation gauge symmetry at huge energies, we have undertaken a large series of numerical simulations with the goal to trace an evolution of the mass assembly history of 377 plausible ...
Gagik Ter-Kazarian, Gary Wegner
wiley +1 more source
Retrograde versus Prograde Models of Accreting Black Holes
Advances in Astronomy, Volume 2013, Issue 1, 2013., 2013 There is a general consensus that magnetic fields, accretion disks, and rotating black holes are instrumental in the generation of the most powerful sources of energy in the known universe. Nonetheless, because magnetized accretion onto rotating black holes involves both the complications of nonlinear magnetohydrodynamics that currently cannot fully be
David Garofalo, Alberto J. Castro-Tirado
wiley +1 more source
M94 as a Unique Testbed for Black Hole Mass Estimates and AGN Activity at Low Luminosities
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 We discuss the peculiar nature of the nucleus of M94 (NGC 4736) in the context of new measurements of the broad Hα emission from HST‐STIS observations. We show that this component is unambiguously associated with the high‐resolution X‐ray, radio, and variable UV sources detected at the optical nucleus of this galaxy.
Anca Constantin +2 more
wiley +1 more source
Recoiling Black Holes: Electromagnetic Signatures, Candidates, and Astrophysical Implications
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 Supermassive black holes (SMBHs) may not always reside right at the centers of their host galaxies. This is a prediction of numerical relativity simulations, which imply that the newly formed single SMBH, after binary coalescence in a galaxy merger, can receive kick velocities up to several 1000 km/s due to anisotropic emission of gravitational waves ...
S. Komossa, Francesca Civano
wiley +1 more source
Probing extreme black‐hole outflows on short timescales via high spectral‐resolution x‐ray imagers
Astronomische Nachrichten, Volume 345, Issue 6-7, July-August 2024.Abstract We investigate outflows and the physics of super‐Eddington versus sub‐Eddington regimes in black hole systems. Our focus is on prospective science using next‐generation high‐resolution soft x‐ray instruments. We highlight the properties of black hole ultraluminous x‐ray source (ULX) systems in particular. Owing to scale invariance in accreting
C. Pinto +9 more
wiley +1 more source
The Cosmic History of Black Hole Growth from Deep Multiwavelength Surveys
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 Significant progress has been made in the last few years on understanding how supermassive black holes form and grow. In this paper, we begin by reviewing the spectral signatures of active galactic nuclei (AGN) ranging from radio to hard X‐ray wavelengths.
Ezequiel Treister +2 more
wiley +1 more source
AGN Obscuration and the Unified Model
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 Unification Models of Active Galactic Nuclei postulate that all the observed differences between type 1 and type 2 objects are due to orientation effects with respect to the line of sight to the observer. The key ingredient of these models is the obscuring medium, historically envisaged as a toroidal structure on a parsec scale.
Stefano Bianchi +3 more
wiley +1 more source
A Practical Guide to the Massive Black Hole Cosmic History
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 I review our current understanding of massive black hole (MBH) formation and evolution along the cosmic history. After a brief introductory overview of the relevance of MBHs in the hierarchical structure formation paradigm, I discuss the main viable channels for seed BH formation at high redshift and for their subsequent mass growth and spin evolution.
A. Sesana, Francesco Shankar
wiley +1 more source
Clustering of X‐Ray‐Selected AGN
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 The study of the angular and spatial structure of the X‐ray sky has been under investigation since the times of the Einstein X‐ray Observatory. This topic has fascinated more than two generations of scientists and slowly unveiled an unexpected scenario regarding the consequences of the angular and spatial distribution of X‐ray sources.
N. Cappelluti +3 more
wiley +1 more source
A Reassessment of the Structure of the Seyfert Galaxy NGC 4151 [PDF]
, 1973 R. D. Davies
openalex +1 more source