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Related papers: Probing the Physics of AGN: A Summary

200 papers

Objective-prism surveys for UV-excess and emission-line objects, especially the First and Second Byurakan Surveys, have been central to the study of active galactic nuclei (AGNs). We review previous line-selected surveys for AGNs and…

Astrophysics · Physics 2007-05-23 Caryl Gronwall , Vicki Sarajedini , John Salzer

Binary black holes (BBHs) in the vicinity of Active Galactic Nuclei (AGNs) are particularly interesting systems from both a cosmological and astrophysical point of view. Matter and radiation fields within the dense AGN environment could…

High Energy Astrophysical Phenomena · Physics 2025-10-27 Leonardo Ricca , Matthias Vereecken , Christoph Raab , Mathieu Lamoureux , Giacomo Bruno , Gwenhaël De Wasseige

We consider the production of high energy neutrinos and cosmic rays in radio-quiet active galactic nuclei (AGN) or in the central regions of radio-loud AGN. We use a model in which acceleration of protons takes place at a shock in an…

Astrophysics · Physics 2010-11-30 A. P. Szabo , R. J. Protheroe

Gas inflows fueling AGN are now traceable at high-resolution with ALMA and NOEMA. Dynamical mechanisms are essential to exchange angular momentum and drive the gas to the super-massive black hole. While at 100pc scale, the gas is sometimes…

Astrophysics of Galaxies · Physics 2021-04-07 F. Combes

This contribution reviews the properties of nuclear activity in nearby galaxies, with emphasis on their implications for the demography of nuclear black holes and the nature of accretion flows in the regime of very low accretion rates.

Astrophysics · Physics 2007-05-23 Luis C. Ho

We are conducting an archival Swift program to measure multiwavelength variability in active galactic nuclei (AGN). This variability information will provide constraints on the geometry, physical conditions and processes of the structures…

High Energy Astrophysical Phenomena · Physics 2015-05-21 Jonathan Gelbord , Caryl Gronwall , Dirk Grupe , Dan Vanden Berk , Jian Wu

Physical processes such as re-ignition, enhancement, and fading of active galactic nuclei (AGN) are not entirely understood because the timeline of these events is expected to last many years. However, it is well known that the differences…

The quest for binary and dual supermassive black holes (SMBHs) at the dawn of the multi-messenger era is compelling. Detecting dual active galactic nuclei (AGN) -- active SMBHs at projected separations larger than several parsecs -- and…

X-ray spectroscopy offers an opportunity to study the complex mixture of emitting and absorbing components in the circumnuclear regions of active galactic nuclei, and to learn about the accretion process that fuels AGN and the feedback of…

High Energy Astrophysical Phenomena · Physics 2009-11-13 T. J. Turner , L. Miller

We present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jonathan R. Trump , Alexander D. Hsu , Jerome J. Fang , S. M. Faber , David C. Koo , Dale D. Kocevski

This Astro2020 white paper summarizes the unknowns of active galactic nuclei (AGN) physics that could be unveiled thanks to a new, space-born, ultraviolet spectropolarimeter. The unique capabilities of high energy polarimetry would help us…

High Energy Astrophysical Phenomena · Physics 2019-03-14 F. Marin , S. Charlot , B. Agís González , D. Sluse , D. Hutsemékers , A. Labiano , L. Grosset , C. Neiner , J. -C. Bouret

Active Galactic Nuclei (AGN) are believed to be powered by accretion of matter onto a supermassive black hole. A fundamental ingredient in shaping our understanding of AGN is their variability across the entire electromagnetic spectrum.…

High Energy Astrophysical Phenomena · Physics 2025-09-08 Maurizio Paolillo , Iossif Papadakis

VLBI observations of relativistic outflows (jets) in galactic nuclei, complemented with detailed studies made in other spectral domains, have become an effective tool for investigating the physics of nuclear regions in galaxies.…

Astrophysics · Physics 2007-09-03 Andrei Lobanov

Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their…

Astrophysics of Galaxies · Physics 2016-05-24 Jinyi Shangguan , Xin Liu , Luis C. Ho , Yue Shen , Chien Y. Peng , Jenny E. Greene , Michael A. Strauss

In this paper I review the recent progress in understanding the physics of the gas outflowing from active galactic nuclei and its impact on the surrounding environment, using the combined information provided by multiwavelength…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Elisa Costantini

Galaxy mergers provide a mechanism for galaxies to effectively funnel gas and materials toward their nuclei and fuel the central starbursts and accretion of supermassive black holes. In turn, the active nuclei drive galactic-scale outflows…

Astrophysics of Galaxies · Physics 2022-07-28 Vivian U

We discuss the very different methods in each wavelength band for selecting and finding Active Galactic Nuclei (AGN). We briefly review the history of the different techniques for finding AGN and compare and contrast the advantages and…

Astrophysics · Physics 2016-01-27 Richard Mushotzky

Active Galactic Nuclei are fueled from material (gas or stars) that are in general far away from the gravitational influence of the central black hole, the engine thought to be responsible for their activity. The required material has a lot…

Astrophysics · Physics 2016-11-03 F. Combes

Various types of active galactic nuclei (AGN) are briefly discussed, with an emphasis on the theory of recent X-ray and $\gamma$-ray observations of the subclass, Seyfert 1 galaxies. The large radiation power from AGN is thought to…

Astrophysics · Physics 2007-05-23 Roland Svensson

Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Loredana Bassani , M. Molina , A. Malizia , F. Panessa , R. Landi , A. Bazzano , P. Ubertini , A. J. Bird , J. B. Stephen