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Related papers: Revealing AGN by Polarimetry

200 papers

Due to the compactness active galactic nuclei (AGNs) are still unresolved with optical observations. However, structure and physical conditions of the matter in their central parts are especially important to study the processes of the…

Astrophysics of Galaxies · Physics 2020-03-31 Elena Shablovinskaya , Viktor Afanasiev

Among all the astronomical sources investigated through the prism of polarimetry, active galactic nuclei (AGN) have proven to be the richest in terms of complex yet fundamental signatures that helped to understand their true nature. Indeed,…

Astrophysics of Galaxies · Physics 2019-09-25 F. Marin

Active galactic nuclei (AGN) produce the highest intrinsic luminosities in the Universe from within a compact region. The central engine is thought to be powered by accretion onto a supermassive black hole. A fraction of this huge release…

Astrophysics of Galaxies · Physics 2018-05-07 Beatriz Agís González , Damien Hutsemékers , Giovanni Miniutti

Optical spectropolarimetry and broadband polarimetry in other wavebands has been a key to understanding many diverse aspects of AGN. In some cases polarization is due to synchrotron radiation, and in other cases it's due to scattering.…

Astrophysics · Physics 2007-05-23 R. R. J. Antonucci

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

The ultraviolet (UV) polarization spectrum of nearby active galactic nuclei (AGN) is poorly known. The Wisconsin Ultraviolet Photo-Polarimeter Experiment and a handful of instruments on board the Hubble Space Telescope were able to probe…

Instrumentation and Methods for Astrophysics · Physics 2018-09-27 F. Marin , S. Charlot , D. Hutsemékers , B. Agís González , D. Sluse , A. Labiano , L. Grosset , C. Neiner , J. -C. Bouret

Was the Milky Way galaxy a low-luminosity active galactic nucleus (AGN) in the past? Can we find traces of remnant structures supporting this idea? What is the three-dimensional arrangement of matter around our central supermassive black…

High Energy Astrophysical Phenomena · Physics 2015-09-22 F. Marin

Active Galactic Nuclei (AGN) are highly energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, which present unique observational signatures covering the full electromagnetic spectrum (and more) over…

High Energy Astrophysical Phenomena · Physics 2023-04-05 Stefano Bianchi , Vincenzo Mainieri , Paolo Padovani

In this paper we give a brief review of the astrophysics of active galactic nuclei (AGN). After a general introduction motivating the study of AGNs, we discuss our present understanding of the inner workings of the central engines, most…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Henric Krawczynski , Ezequiel Treister

A crucial difficulty in understanding the nature of the putative accretion disk in AGNs is that some of its key intrinsic spectral signatures cannot be observed directly. The strong emissions from the broad-line region (BLR) and the…

One primary difficulty in understanding the nature of the putative accretion disk in the central engine of AGNs is that some of its key intrinsic spectral signatures are buried under the emissions from the surrounding regions, i.e. the…

Astrophysics · Physics 2007-05-23 Makoto Kishimoto , Robert Antonucci , Omer Blaes

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

The black-hole/accretion-disk paradigm for active galactic nuclei (AGNs) is now reasonably secure, but there are still important unresolved issues, some of which will require the capabilities of an 8 to 10-m class UV/optical space-based…

Astrophysics · Physics 2007-05-23 Bradley M. Peterson

Most Active Galactic Nuclei (AGN) are `obscured', i.e. the nucleus is hiding behind a screen of absorbing material. The advantage of having the nucleus obscured is to make easier the observations of those emission components which originate…

Astrophysics · Physics 2009-11-07 G. Matt

Observing programs comprising multiple scientific objectives will enhance the productivity of NASA's next UV/Visible mission. Studying active galactic nuclei (AGN) is intrinsically important for understanding how black holes accrete matter,…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-17 Gerard Kriss , Nahum Arav , Anton Koekemoer , Smita Mathur , Bradley M. Peterson , Jennifer E. Scott

A thermal active galactic nucleus (AGN) consist of a powerful, broad-band continuum source that is surrounded by several reprocessing media with different geometries and compositions. Here we investigate the expected spectropolarimetric…

High Energy Astrophysical Phenomena · Physics 2012-04-05 Frederic Marin , Rene W. Goosmann

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

We discuss the polarization of broad emission lines in the type 1 active galactic nuclei (AGNs). The polarization depends on the geometry of the broad line region (BLR), and also on the polarization mechanism, or distribution of the…

Astrophysics of Galaxies · Physics 2021-11-12 L. C. Popović , E. Shablovinskaya , Dj. Savić

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

Optical polarization signal coming from the innermost part of active galactic nuclei (AGNs) is highly sensitive on the geometry and kinematics of the central engine. Due to the compact size of the AGN central region, which is spatially…

Astrophysics of Galaxies · Physics 2019-04-01 Đorđe Savić
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