Results 31 to 40 of about 160 (135)
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
Microvariability in Seyfert Galaxies
The Astronomical Journal, 2003 We present the results of a search for microvariability in a sample of eight Seyfert galaxies. Microvariability (i.e., variations occurring on timescales of tens of minutes to hours) has been conclusively demonstrated to exist in the class of active galactic nuclei (AGNs) known as blazars. Its existence in other classes of AGNs is far less certain.
M. T. Carini, J. C. Noble, H. R. Miller
openaire +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
THE MID-INFRARED CONTINUA OF SEYFERT GALAXIES [PDF]
The Astrophysical Journal, 2009 25 pages, 3 tables, 11 figures; Accepted for Publication in Nov.
Deo, Rajesh. P. +3 more
openaire +2 more sources
Physik in unserer Zeit, Volume 56, Issue 1, Page 30-37, January 2025.Galaxien wie die Milchstraße sind umhüllt von einem gigantischen Kokon aus diffusem Gas. Aktuelle Forschungsergebnisse belegen, dass dieses zirkumgalakische Medium eine entscheidende Rolle für die Entstehung und Entwicklung von Galaxien spielt. Zusammenfassung Als zirkumgalaktisches Medium bezeichnet man die gasförmigen Hüllen von Galaxien, die sich ...
Philipp Richter
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
Spitzer spectra of Seyfert galaxies
, 2009 to appear in the proceedings of "The Starburst-AGN Connection Conference", Shanghai, China, 27 Oct - 1 Nov 2008, ASP Conference ...
Spinoglio, Luigi +3 more
openaire +3 more sources
On X‐Ray Variability in Seyfert Galaxies [PDF]
The Astrophysical Journal, 1999 11 pages, 1 figure 1 table. LaTeX with encapsulated postscript. Accepted for publication in the Astrophysical Journal. Replaced first version to fix a printing problem caused by the figure.
Turner, T. J. +3 more
openaire +2 more sources
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