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Related papers: Depolarization and Faraday effects in AGN Jets

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Synchrotron self-absorption in active galactic nuclei (AGN) jets manifests itself as a time delay between flares observed at high and low radio frequencies. It is also responsible for the observing frequency dependent change in size and…

Astrophysics of Galaxies · Physics 2019-04-17 Alexander Kutkin , Ilya Pashchenko , Kirill Sokolovsky , Yuri Y. Kovalev , Margo Aller , Hugh Aller

In recent studies, several AGN have exhibited gradients of the Faraday Rotation Measure (RM) transverse to their parsec-scale jet direction. Faraday rotation likely occurs as a result of a magnetized sheath wrapped around the jet. In the…

High Energy Astrophysical Phenomena · Physics 2021-03-26 M. M. Lisakov , E. V. Kravchenko , A. B. Pushkarev , Y. Y. Kovalev , T. K. Savolainen , M. L. Lister

Distributions of Faraday rotation measure (FRM) and the projected magnetic field derived by a 3-dimensional simulation of MHD jets are investigated based on our "sweeping magnetic twist model". FRM and Stokes parameters were calculated to…

Astrophysics · Physics 2009-11-10 H. Kigure , Y. Uchida , M. Nakamura , S. Hirose , R. Cameron

The phenomenon of Faraday rotation of linearly polarized synchrotron emission in a magneto-ionized medium has been understood and studied for decades. But since the sense of the rotation itself is irrelevant in most contexts, some…

Astrophysics of Galaxies · Physics 2021-07-14 K. Ferrière , J. L. West , T. R. Jaffe

Non-VLBI measurements of Faraday rotation at mm wavelengths have been used to constrain mass accretion rates ($\mdot$) onto supermassive black holes in the centre of the Milky Way and in the centre of M87. We constructed general…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Monika Moscibrodzka , Jason Dexter , Jordy Davelaar , Heino Falcke

Fast Radio Bursts (FBRs) show highly different polarization properties: high/small RMs, high/small circular/linear fractions. We outline a complicated picture of polarization propagation in the inner parts of the magnetars' winds, at scales…

High Energy Astrophysical Phenomena · Physics 2022-06-08 Maxim Lyutikov

We calculate the polarization of radiation from thick accretion disks with vertically averaged global magnetic field. The polarization arises as a result of the radiation scattering by free electrons in magnetized plasma of a disk. We…

Astrophysics · Physics 2007-05-23 Yu. N. Gnedin , N. A. Silant'ev , P. S. Shternin

We used 15 GHz multi-epoch Very Long Baseline Array (VLBA) polarization sensitive observations of 484 sources within a time interval 1996--2016 from the MOJAVE program, and also from the NRAO data archive. We have analyzed the linear…

High Energy Astrophysical Phenomena · Physics 2017-12-11 A. B. Pushkarev , Y. Y. Kovalev , M. L. Lister , T. Savolainen , M. F. Aller , H. D. Aller , M. A. Hodge

Outflows driven by active galactic nuclei (AGN) are seen in numerous compact sources; however, it has remained unclear how to distinguish between the driving mechanisms, such as winds and jets. Therefore, our study aims to offer…

High Energy Astrophysical Phenomena · Physics 2024-08-02 Moun Meenakshi , Dipanjan Mukherjee , Gianluigi Bodo , Paola Rossi , Chris M. Harrison

The analysis of the frequency dependence of the observed shift of the cores of relativistic jets in active galactic nuclei (AGN) allows us to evaluate the number density of the outflowing plasma n and, hence, the multiplicity parameter,…

High Energy Astrophysical Phenomena · Physics 2015-01-13 E. E. Nokhrina , V. S. Beskin , Y. Y. Kovalev , A. A. Zheltoukhov

We investigate the emission properties that a large-scale helical magnetic field imprints on AGN jet synchrotron radiation. A cylindrically symmetric relativistic jet and large-scale helical magnetic field produce significant asymmetrical…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Eric Clausen-Brown , Maxim Lyutikov , Preeti Kharb

Polarization has proved an invaluable tool for probing magnetic fields in relativistic jets. Maps of the intrinsic polarization vectors have provided the best evidence to date for uniform, toroidally dominated magnetic fields within jets.…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Avery E Broderick , Abraham Loeb

Very long baseline interferometry (VLBI) observations show that some active galactic nuclei (AGN) jets exhibit bending even at parsec scales. The nature of bending is comprehensively analysed only for a small number of individual AGN, and…

High Energy Astrophysical Phenomena · Physics 2023-10-05 V. A. Makeev , Y. Y. Kovalev , A. B. Pushkarev

Generalised Faraday rotation can induce frequency-dependent conversion between the linear and circular polarisation spectra of compact radio sources such as pulsars, fast radio bursts and active galactic nuclei. I devise a simple…

High Energy Astrophysical Phenomena · Physics 2021-08-24 Marcus E. Lower

We present an analysis of the core linear polarization properties of 387 parsec-scale active galactic nuclei (AGN) jets. Using 15 GHz VLBA data, we revisit the conclusions of the first paper in this series with multi-epoch measurements and…

Astrophysics of Galaxies · Physics 2018-08-16 M. A. Hodge , M. L. Lister , M. F. Aller , H. D. Aller , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

Radio emission in blazars -- the aligned subset of Active Galactic Nuclei (AGN) -- is produced by synchrotron electrons moving relativistically in their jet's magnetic field. Under the assumption of some degree of uniformity of the field,…

High Energy Astrophysical Phenomena · Physics 2014-04-09 I. Myserlis , E. Angelakis , L. Fuhrmann , V. Pavlidou , I. Nestoras , V. Karamanavis , A. Kraus , J. A. Zensus

We present Faraday Rotation Measure (RM) properties of seven active galactic nuclei (AGN), observed with the NRAO VLA at three epochs in 2012-2014. Data was taken at 1.4, 2.2, 5.0, 8.2, 15.4, 22.4, 33.5 and 43.1 GHz quasi simultaneously in…

High Energy Astrophysical Phenomena · Physics 2015-06-23 E. V. Kravchenko , W. D. Cotton , Y. Y. Kovalev

We studied the polarization behavior of the quasar 3C 273 over the 1 mm wavelength band at ALMA with a total bandwidth of 7.5GHz across 223 to 243 GHz at 0.8 arcsec resolution, corresponding to 2.1 kpc at the distance of 3C 273. With these…

Astrophysics of Galaxies · Physics 2019-03-13 T. Hovatta , S. O'Sullivan , I. Martí-Vidal , T. Savolainen , A. Tchekhovskoy

One of the tools that can provide evidence about the existence of helical magnetic fields in AGN is the observation of rotation measure gradients across the jet. Such observations have been previously made successfully, proving that such…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 J. C. Algaba

Using stacking of images obtained at different epochs, we studied the variability properties of linear polarization of active galactic nucleus (AGN) jets on parsec-scales. Our sample is drawn from the MOJAVE programme, and consists of 436…

High Energy Astrophysical Phenomena · Physics 2023-06-16 D. I. Zobnina , H. D. Aller , M. F. Aller , D. C. Homan , Y. Y. Kovalev , M. L. Lister , I. N. Pashchenko , A. B. Pushkarev , T. Savolainen
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