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Related papers: Polarization of AGN Jets

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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

Radio interferometric observations of Active Galactic Nuclei (AGN) jets reveal the significant linear polarization of their synchrotron radiation that changes with frequency due to the Faraday rotation. It is generally assumed that such…

Astrophysics of Galaxies · Physics 2024-11-06 E. Yushkov , I. N. Pashchenko , D. D. Sokoloff , G. Chumarin

We discuss a new VLBA program to investigate structural and polarization changes in the brightest AGN jets in the northern sky. Our study represents a significant improvement over previous surveys in terms of image fidelity, size, and…

Astrophysics · Physics 2007-05-23 M. L. Lister

A single measurement of linear polarization of a nonthermal source provides direct information about the mean direction and level of ordering of the magnetic field. Monitoring of the polarization in blazars, combined with millimeter-wave…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Alan P. Marscher

Multi-frequency (4.6, 5, 5.5, 8, 8.8, 13, 15, 22 & 43 GHz) polarization observations of 6 "blazars" were obtained on the American Very Long Baseline Array (VLBA) over a 24-hr period on 2 July 2006. Observing at several frequencies,…

Astrophysics · Physics 2009-11-13 Shane P. O'Sullivan , Denise C. Gabuzda

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

Here, we demonstrate that polarization properties show a wide diversity depending on viewing angles. To simulate images of a supermassive black hole and surrounding plasma, we performed a full-polarimetric general relativistic radiative…

High Energy Astrophysical Phenomena · Physics 2022-10-25 Yuh Tsunetoe , Shin Mineshige , Tomohisa Kawashima , Ken Ohsuga , Kazunori Akiyama , Hiroyuki R. Takahashi

Relatively few Very Long Baseline Interferometry (VLBI) polarization observations have been carried out at 18 cm. The importance of such observations lies in their ability to reveal information about the jet magnetic ({\bf B}) field…

Astrophysics · Physics 2007-08-01 Péter Veres , Denise C. 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

We perform polarimetry analysis of 20 active galactic nuclei (AGN) jets using the Very Long Baseline Array (VLBA) at 1.4, 1.6, 2.2, 2.4, 4.6, 5.0, 8.1, 8.4, and 15.4 GHz. The study allowed us to investigate linearly polarized properties of…

High Energy Astrophysical Phenomena · Physics 2018-03-12 E. V. Kravchenko , Y. Y. Kovalev , K. V. Sokolovsky

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

We present circular polarization results from a 5 GHz survey of the parsec-scale polarization properties of 40 AGN made with the VLBA. We find 11 circular polarization detections at the 3 sigma level or higher. This nearly quadruples the…

Astrophysics · Physics 2009-11-06 Daniel C. Homan , Joanne M. Attridge , John F. C. Wardle

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

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

Evidence that the magnetic fields of extragalactic jets have a significant fraction of their energy in a random component is briefly summarized, and a detailed model of evolving, jet polarization structures is constructed, based on this…

Astrophysics · Physics 2009-11-10 Philip A. Hughes

Millimeter-band polarimetry offers a powerful probe of AGN jets, accessing regions less affected by opacity and Faraday rotation than at longer radio wavelengths. As part of the POLAMI program, we have conducted 14 years of 1 mm and 3 mm…

We present analysis of the flux and polarization variability of parsec scale radio jets from a dual-frequency, six-epoch, VLBA polarization experiment monitoring 12 blazars. The observations were made at 15 and 22 GHz at bimonthly intervals…

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

We aim to better understand the dynamics within relativistic magneto-hydrodynamical flows in the extreme environment and close vicinity of supermassive black holes. To do so, we analyze the peculiar radio galaxy 3C 111, for which long-term…

We interpret the linear polarization structures observed in extragalactic radio sources, even those oriented at oblique angles to the jet flows, to be due to oblique, relativistic shock fronts in the emitting regions. Many sources exhibit…

Astrophysics · Physics 2007-05-23 H. D. Aller , M. F. Aller , P. A. Hughes
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