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Related papers: Active Galactic Nuclei in polarized light

200 papers

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…

We have used the STOKES radiative transfer code, to model polarization induced by dust scattering in the polar regions of Active Galactic Nuclei (AGN). We discuss the wavelength-dependence of the spectral intensity and polarization over the…

Astrophysics · Physics 2007-05-23 Rene W. Goosmann , C. Martin Gaskell , M. Shoji

We discuss the constraints that recent observations place on circular polarization in AGN. In many sources the circular polarization is variable on short timescales, indicating that it originates in compact regions of the sources. The best…

Astrophysics · Physics 2007-05-23 J. -P. Macquart

When and how did galaxies form and their metals accumulate? Over the last decade, this has moved from an archeological question to a live investigation: there is now a broad picture of the evolution of galaxies in dark matter halos: their…

Most of the action in Active Galactic Nuclei (AGN) occurs within a few tens of gravitational radii from the supermassive black hole, where matter in the accretion disk may lose up to almost half of its energy with a copious production of…

Infrared (IR) interferometry has made widely recognised contributions to the way we look at the dusty environment of supermassive black holes on parsec scales. It finally provided direct evidence for orientation-dependent unification of…

We present a study of the connection between black hole accretion, star formation, and galaxy morphology at z<=2.5. We focus on active galactic nuclei (AGNs) selected by their mid-IR power-law emission. By fitting optical to far-IR…

Context: Active galactic nuclei (AGN) are anisotropic objects surrounded by an optically thick equatorial medium whose true geometry still defy observers. Aims: In this paper, we aim to explore the optical, scattering-induced, polarization…

Astrophysics of Galaxies · Physics 2017-11-15 F. Marin , M. Schartmann

The nature of the obscuring material in active galactic nuclei is still uncertain. Although some sources, such as Cygnus A, show evidence for a geometrically thick ``torus'' as originally suggested, recent work on the radiation-driven…

Astrophysics · Physics 2007-05-23 Philip R. Maloney

With the observation of gravitational waves from merging compact binary systems, a new observing window of the universe has been opened. Most of the gravitational wave events currently detected are due to the merger of binary black hole…

High Energy Astrophysical Phenomena · Physics 2023-10-03 Giacomo Bruno , Gwenhaël De Wasseige , Romain Gorski , Mathieu Lamoureux , Matthias Vereecken

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

Supermassive black holes (SMBHs) have been detected in the centers of most nearby massive galaxies. Galaxies today are the products of billions of years of galaxy mergers, but also billions of years of SMBH activity as active galactic…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-05 Sandor Van Wassenhove , Marta Volonteri , Lucio Mayer , Massimo Dotti , Jillian Bellovary , Simone Callegari

We study the benefits of polarimetry observations of microlensing events to detect and characterize circumstellar disks around the microlensed stars located at the Galactic bulge. These disks which are unresolvable from their host stars…

Solar and Stellar Astrophysics · Physics 2016-05-11 Sedighe Sajadian , Sohrab Rahvar

We have studied the linear polarization of 86 active galactic nuclei (AGN) in the observed frequency range 80-267 GHz (3.7-1.1mm in wavelength), corresponding to rest-frame frequencies 82-738 GHz, with the IRAM Plateau de Bure…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. Trippe , R. Neri , M. Krips , A. Castro-Carrizo , M. Bremer , V. Pietu , A. L. Fontana

A close-in giant planetary (CGP) system has a net polarization signal whose value varies depending on the orbital phase of the planet. This polarization signal is either caused by the stellar occultation or by reflected starlight from the…

Earth and Planetary Astrophysics · Physics 2017-04-07 Sedighe Sajadian , Markus Hundertmark

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

The magnetic field is believed to play a critical role in the bulk acceleration and propagation of jets produced in active galactic nuclei (AGN). Polarization observations of AGN jets provide valuable information about their magnetic…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Jongho Park , Juan Carlos Algaba

Active Galactic Nuclei (AGN) are remarkable astronomical sources emitting over the whole electromagnetic spectrum, with different bands providing unique windows on distinct sub-structures and their related physics. AGN come in a large…

High Energy Astrophysical Phenomena · Physics 2023-02-27 Paolo Padovani

The main requirements for fueling an active galactic nucleus and to form massive black holes are reviewed. Low-luminosity AGN can be fueled easily from the local star clusters, near the nucleus, and the various stellar processes are…

Astrophysics · Physics 2007-05-23 F. Combes

Low-Luminosity Active Galactic Nuclei (LLAGN) provides a unique view of Comptonization and non-thermal emission from accreting black holes in the low-accretion rate regime. However, to decipher the exact nature of the Comptonizing corona in…