Results 1 to 10 of about 230,356 (290)
Proc Natl Acad Sci U S A, 1999 Active galactic nuclei are the most powerful, long-lived objects in the Universe. Recent data confirm the theoretical idea that the power source is accretion into a massive black hole. The common occurrence of obscuration and outflows probably means that the contribution of active galactic nuclei to the power density of the Universe has been ...
Fabian AC.
europepmc +8 more sources
Active Galactic Nuclei Search [PDF]
Atoms, 2017 We present the first results of medium-band photometric observations on the 1m Schmidt Telescope of Byurakan Astrophysical Observatory (Armenia). The object sample was created in the SA68 field.
Sergey Kotov, Sergey Dodonov
doaj +2 more sources
Reionization with galaxies and active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 ABSTRACT In this work we investigate the properties of the sources that reionized the intergalactic medium (IGM) in the high-redshift Universe. Using a semi-analytical model aimed at reproducing galaxies and black holes in the first ∼1.5 Gyr of the Universe, we revisit the relative role of star formation and black hole accretion in ...
Tirthankar Roy Choudhury +12 more
openaire +7 more sources
Obscured Active Galactic Nuclei [PDF]
Annual Review of Astronomy and Astrophysics, 2018 Active galactic nuclei (AGN) are powered by the accretion of material onto a supermassive black hole (SMBH) and are among the most luminous objects in the Universe. However, the huge radiative power of most AGN cannot be seen directly, as the accretion is hidden behind gas and dust that absorb many of the characteristic observational signatures.
Hickox, R.C, Alexander, D.M.
openaire +6 more sources
Flux States of Active Galactic Nuclei [PDF]
Galaxies, 2019 Blazars are known to show variability on time scales from minutes to years covering a wide range of flux states. Studying the flux distribution of a source allows for various insights.
Daniela Dorner +28 more
doaj +6 more sources
Active galactic nuclei: what’s in a name? [PDF]
The Astronomy and Astrophysics Review, 2017 Accepted for publication in Astronomy & Astrophysics Review, 56 pages, 25 ...
P. Padovani +10 more
openaire +5 more sources
Questions and challenges of what powers galactic outflows in active galactic nuclei [PDF]
, 2018 Different mechanisms can drive outflows in active galactic nuclei (AGN), but it is often unclear which mechanism dominates, if any. To quantify the impact of AGN feedback on galaxy evolution, the driving mechanism of outflows must be better understood.
Dominika Wylezalek, R. Morganti
arxiv +3 more sources
Reconfinement and Loss of Stability in Jets from Active Galactic Nuclei [PDF]
Nature Astronomy volume 2, pages 167-171 (2018), 2018 Jets powered by active galactic nuclei appear impressively stable compared with their terrestrial and laboratory counterparts-they can be traced from their origin to distances exceeding their injection radius by up to a billion times. However, some less energetic jets get disrupted and lose their coherence on the scale of their host galaxy.
K. Gourgouliatos, S. Komissarov
arxiv +3 more sources
Reverberation Mapping of Active Galactic Nuclei [PDF]
Astronomische Nachrichten, 2004 Reverberation mapping is a proven technique that is used to measure the size of the broad emission-line region and central black hole mass in active galactic nuclei. More ambitious reverberation mapping programs that are well within the capabilities of Hubble Space Telescope could allow us to determine the nature and flow of line-emitting gas in active
Keith Horne, Bradley M. Peterson
arxiv +5 more sources
Spin Evolution of Stellar-mass Black Hole Binaries in Active Galactic Nuclei [PDF]
Astrophysical Journal, 2020 The astrophysical origin of gravitational-wave (GW) events is one of the most timely problems in the wake of the LIGO/Virgo discoveries. In active galactic nuclei (AGNs), binaries form and evolve efficiently by dynamical interactions and gaseous ...
H. Tagawa +3 more
semanticscholar +1 more source