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Related papers: Depolarization and Faraday effects in AGN Jets

200 papers

We investigate the effect of the jet's immediate surroundings on the non-thermal synchrotron emission and its polarization properties. The ambient medium is equipped with a turbulent magnetic field, which is compressed and amplified by the…

High Energy Astrophysical Phenomena · Physics 2023-10-06 Moun Meenakshi , Dipanjan Mukherjee , Gianluigi Bodo , Paola Rossi

Preliminary VLBA polarisation results on 6 ``blazars'' from 6.5-cm to 7-mm are presented here. Observing at several different wavelengths, separated by short and long intervals, enabled reliable information about the magnetic (B) field…

Astrophysics · Physics 2007-10-02 Shane P. O'Sullivan , Denise C. Gabuzda

Several multi-frequency polarization studies have shown the presence of systematic Faraday Rotation gradients across the parsec-scale jets of Active Galactic Nuclei (AGN), taken to be due to the systematic variation of the line-of-sight…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. Mahmud , D. C. Gabuzda , V. Bezrukovs

We are using "broadband" (4.6 to 43 GHz) multi-frequency VLBA polarization observations of compact AGN to investigate the 3-D structure of their jet magnetic (B) fields. Observing at several frequencies, separated by short and long…

Astrophysics · Physics 2008-02-01 Shane P. O'Sullivan , Denise C. Gabuzda

The magnetic field plays a significant role in the phenomenon of highly collimated jets of active galactic nuclei (AGN). Relativistic effects prevent the direct reconstruction of the magnetic field direction as transverse to electric…

High Energy Astrophysical Phenomena · Physics 2023-03-01 Marina S. Butuzova , Alexander B. Pushkarev

A joint action of depth and bandwidth depolarization in the interstellar medium is considered using a model of N homogeneous synchrotron layers with Faraday rotation. The bandwidth depolarization can be used in multifrequency polarimetric…

Astrophysics · Physics 2007-05-23 E. N. Vinyajkin

Both the emission properties and evolution of Active Galactic Nuclei (AGN) radio jets are dependent on the magnetic (B) fields that thread them. Faraday Rotation measurements are a very important way of investigating these B fields, and can…

High Energy Astrophysical Phenomena · Physics 2013-09-09 Eoin Murphy , Colm Coughlan , Denise Gabuzda

The latest results of the most detailed analysis of multi-epoch polarization-sensitive observations of active galactic nuclei (AGN) jets at parsecs scales by very long baseline interferometry (VLBI) reveal several characteristic patterns of…

High Energy Astrophysical Phenomena · Physics 2024-02-13 R. V. Todorov , E. V. Kravchenko , I. N. Pashchenko , A. B. Pushkarev

In inhomogeneous optically thick synchrotron sources a substantial part of the electron population at low energies can be hidden by self-absorption and overpowered by high energy electrons in optically thin emission. These invisible…

Astrophysics · Physics 2009-11-07 Thomas Beckert , Heino Falcke

We study parity-violating birefringence induced by an asymmetric neutrino background in plasmas associated with active galactic nuclei (AGN). We derive a directionality factor arising from the relative bulk motion between the neutrino…

High Energy Physics - Phenomenology · Physics 2026-01-23 H. B. Câmara , A. Smetana , A. Tursunov

Parsec-scale multi-wavelength VLBA polarization observations can be used to study the magnetic-field structures of Active Galactic Nuclei (AGN) based on Faraday Rotation (FR) gradients. A number of transverse FR gradients have been found,…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-15 Mehreen Mahmud , Denise C. Gabuzda

Faraday rotation is an important probe of the magnetic fields and magnetized plasma around active galactic nuclei (AGN) jets. We present a Faraday rotation measure image of the M87 jet between 85.2 GHz and 101.3 GHz with a resolution of ~2"…

(Abridged) We consider the polarization properties of optically thin synchrotron radiation emitted by relativistically moving electron--positron jets carrying large-scale helical magnetic fields. In our model, the jet is cylindrical, and…

Astrophysics · Physics 2009-11-10 Maxim Lyutikov , Vladimir I. Pariev , Denise C. Gabuzda

The idea that systematic Faraday Rotation gradients across the parsec-scale jets of AGNs can reveal the presence of helical magnetic (B) fields has been around since the early 1990s. These gradients are taken to be due to the systematic…

High Energy Astrophysical Phenomena · Physics 2019-08-19 Mehreen Mahmud , Colm P. Coughlan , Eoin Murphy , Denise C. Gabuzda , Redmond Hallahan

We present the results from a broadband (1 to 3 GHz), spectro-polarimetry study of the integrated emission from 100 extragalactic radio sources with the ATCA, selected to be highly linearly polarized at 1.4 GHz. We use a general purpose,…

Astrophysics of Galaxies · Physics 2017-06-28 S. P. O'Sullivan , C. R. Purcell , C. S. Anderson , J. S. Farnes , X. H. Sun , B. M. Gaensler

Relativistic jets are one of the most powerful manifestations of the release of energy produced around supermassive black holes at the centre of active galactic nuclei (AGN). Their emission is observed across the entire electromagnetic…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Orienti , F. D'Ammando , M. Giroletti , D. Dallacasa , T. Venturi , G. Giovannini

Many quasars and active galactic nuclei (AGN) appear in radio, optical, and X-ray maps, as a bright nuclear sources from which emerge single or double long, thin jets. When observed with high angular resolution these jets show structure…

Astrophysics · Physics 2008-11-26 Gennady Bisnovatyi-Kogan

Contopoulos et al. recently argued that there is observational evidence for a preferred sense of the Faraday rotation-measure gradients across jets from active galactic nuclei (AGNs). Such behaviour could arise if there were a deterministic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Arieh Königl

Wide-band radio polarization observations offer the possibility to recover information about the magnetic fields in synchrotron sources, such as details of their three-dimensional configuration, that has previously been inaccessible. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Cathy Horellou , Andrew Fletcher

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