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Related papers: Selected Chapters on Active Galactic Nuclei as Rel…

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Recent astronomical observations reveal that Active Galactic Nuclei (AGN) are sources of high-energy radiation. For example, the Fermi-LAT and Hess telescopes have detected gamma-ray emissions from the cores of several types of AGN's. Even…

High Energy Astrophysical Phenomena · Physics 2013-08-15 J. C. Arteaga-Velazquez , Angelo Martinez

Active galactic nuclei (AGN) are complex phenomena. At the heart of an AGN is a relativistic accretion disk around a spinning supermassive black hole (SMBH) with an X-ray emitting corona and, sometimes, a relativistic jet. On larger scales,…

High Energy Astrophysical Phenomena · Physics 2016-05-25 Christopher S. Reynolds

Bright Active Galactic Nuclei are powered by accretion of mass onto the super massive black holes at the centers of the host galaxies. For fainter objects star formation may significantly contribute to the luminosity. We summarize…

Galactic outflows, driven by active galactic nuclei (AGN), play a crucial role in galaxy formation and in the self-regulated growth of supermassive black holes (BHs). AGN feedback couples to and affects gas, rather than stars, and in many,…

Astrophysics of Galaxies · Physics 2018-04-10 Tilman Hartwig , Marta Volonteri , Gohar Dashyan

Observations made during the last ten years with the Chandra X-ray Observatory have shed much light on the cooling gas in the centers of clusters of galaxies and the role of active galactic nucleus (AGN) heating. Cooling of the hot…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 Elizabeth L. Blanton , T. E. Clarke , Craig L. Sarazin , Scott W. Randall , Brian R. McNamara

We consider the emission of high energy to very high energy $\gamma$-rays in radio-quiet active galactic nuclei (AGN) or the central regions of radio-loud AGN. We use our results to estimate the $\gamma$-ray flux from the central regions of…

Astrophysics · Physics 2011-05-12 P. A. Johnson , A. Mastichiadis , R. J. Protheroe , T. S. Stanev , A. P. Szabo

In these proceedings I briefly: (1) review the impact (or "feedback") that active galactic nuclei (AGN) are predicted to have on their host galaxies and larger scale environment, (2) review the observational evidence for or against these…

Astrophysics of Galaxies · Physics 2015-06-18 C. M. Harrison

According to the currently favored picture, relativistic jets in active galactic nuclei (AGN) are launched in the vicinity of the black hole by magnetic fields extracting energy from the spinning black hole or the accretion disk. In the…

High Energy Astrophysical Phenomena · Physics 2017-06-28 Talvikki Hovatta

The 2006 meeting in Xi'an on the Central Engine of Active Galactic Nuclei covered the enormous and continuously expanding area of AGN research, from theory to the most sophisticated observations and from gamma-ray energies to long radio…

Astrophysics · Physics 2007-05-23 Hagai Netzer , Joseph C. Shields

This paper summarizes the observations which provide the best evidence for the presence of black holes in active galactic nuclei. This includes: X-ray variability; kinematical studies using optical emission lines as well as the distribution…

Astrophysics · Physics 2007-05-23 Greg M. Madejski

The active galactic nucleus (AGN) phenomena results from a supermassive black hole accreting its surrounding gaseous and dusty material. The infrared (IR) regime provides most of the information to characterize the dusty structures that…

Astrophysics of Galaxies · Physics 2022-05-31 Jianwei Lyu , George Rieke

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…

Astrophysics of Galaxies · Physics 2018-10-17 Ryan C. Hickox , David M. Alexander

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…

Astrophysics of Galaxies · Physics 2018-03-01 Dominika Wylezalek , Raffaella Morganti

(Context) Central active galactic nuclei (AGN) are supposed to play a key role in the evolution of their host galaxies. In particular, the dynamical and physical properties of the gas core must be affected by the injected energy. (Aims) Our…

Astrophysics · Physics 2015-06-24 Sebastien Peirani , Scott Kay , Joe Silk

There are several key open questions as to the nature and origin of AGN including: 1) what initiates the active phase, 2) the duration of the active phase, and 3) the effect of the AGN on the host galaxy. Critical new insights to these can…

Instrumentation and Methods for Astrophysics · Physics 2009-04-27 Steve Kraemer , Rogier Windhorst , Kenneth G. Carpenter , Mike Crenshaw , Martin Elvis , Margarita Karovska

Active Galactic Nuclei (AGNs) emit substantial fluxes of high-energy electromagnetic radiation, and have therefore attracted some recent attention for their negative impact on galactic habitability. In this paper, we propose that AGNs may…

Earth and Planetary Astrophysics · Physics 2019-05-28 Manasvi Lingam , Idan Ginsburg , Shmuel Bialy

A summary critique is presented of the topics discussed at a workshop entitled ``Probing the Physics of Active Galactic Nuclei by Multi-wavelength Monitoring'' held at Goddard Space Flight Center 21-23 June 2000. Particular emphasis is…

Astrophysics · Physics 2007-05-23 R. D. Blandford

Active Galactic Nuclei (AGN) are multiwavelength emitters. To have any hope of understanding them, or even to determine their energy output, we must observe them with many telescopes. I will review what we have learned from broad-band…

Astrophysics · Physics 2007-05-23 Belinda J. Wilkes

In this chapter, I review the fueling and evolution of active galactic nuclei (AGN) under the influence of internal and external triggers, namely intrinsic properties of host galaxies (morphological or Hubble type, color, presence of bars…

Astrophysics · Physics 2008-11-26 Shardha Jogee

We examine all possible stationary, optically thick, geometrically thin accretion disc models relevant for active galactic nuclei (AGN) and identify the physical regimes in which they are stable against the thermal-viscous hydrogen…

Astrophysics · Physics 2015-06-24 L. Burderi , A. R. King , E. Szuszkiewicz