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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

Results from a survey of the parsec scale Faraday rotation measure properties for 40 quasars, radio galaxies and BL Lac objects are presented. Core rotation measures for quasars vary from approximately 500 to several thousand radians per…

Astrophysics · Physics 2009-11-10 R. T. Zavala , G. B. Taylor

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

Multifrequency polarimetric observations made with the Very Long Baseline Array of the quasar 3C216 reveal the presence of Faraday rotation measures (RMs) in excess of 2000 rad/m**2 in the source rest frame, in the arc of emission located…

Astrophysics · Physics 2009-10-31 T. Venturi , G. B. Taylor

We report observations of Faraday rotation measures (RMs) for a sample of 191 extragalactic radio jets observed within the MOJAVE program. Multifrequency VLBA observations were carried out over twelve epochs in 2006 at four frequencies…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-12 T. Hovatta , M. L. Lister , M. F. Aller , H. D. Aller , D. C. Homan , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

Parsec-scale Faraday rotation measure (RM) maps are presented for the radio galaxies M87, 3C 111, and 3C 120. These Very Long Baseline Array observations were made at 8, 12, and 15 GHz. M87 has an extreme RM distribution that varies from…

Astrophysics · Physics 2009-11-07 R. T. Zavala , G. B. Taylor

The parsec-scale Faraday rotation measure (RM) distribution of six "blazars" is investigated using multi-frequency (4.6--43 GHz) polarization observations taken on 2006 July 2 with the VLBA. Analysis of the RM provides the direction of the…

Astrophysics · Physics 2009-02-11 Shane P. O'Sullivan , Denise C. Gabuzda

We have studied Very Long Baseline Array (VLBA) polarimetric observations of 8 sources including quasars and BL Lacs at 12, 15, 22, 24 and 43 GHz and high frequency rotation measure ($RM$) maps are presented. We find typical values for the…

High Energy Astrophysical Phenomena · Physics 2015-06-12 J. C. Algaba

Global VLBI (EVN+VLBA) polarization observations at 5 and 8.4 GHz of ten high redshift (z > 3) quasars are presented. The core and jet brightness temperatures are found through modelling the self-calibrated uv-data with Gaussian components,…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-13 Shane P. O'Sullivan , Denise C. Gabuzda , Leonid I. Gurvits

Using high frequency (12-22 GHz) VLBA observations we confirm the existence of a Faraday rotation measure gradient of ~ 500 rad/m^2/mas transverse to the jet axis in the quasar 3C 273. The gradient is seen in two epochs spaced roughly six…

Astrophysics · Physics 2009-11-11 R. T. Zavala , G. B. Taylor

We present sub-milliarcsecond resolution total intensity and linear polarization VLBI images of 3C273, using concurrent 43 and 86 GHz data taken with the Very Long Baseline Array in May 2002. The structure seen in the innermost jet suggest…

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

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

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

Previously, a multi-wavelength (2cm, 4cm and 6cm) polarization study by Gabuzda, Murray and Cronin (2004) showed systematic Faraday Rotation gradients across the parsec-scale jets of several BL Lac objects, interpreted as evidence for…

Astrophysics · Physics 2007-08-03 Mehreen Mahmud , Denise Gabuzda

Multi-frequency Very Long Baseline Array (VLBA) polarimetry observation of the GHz-Peaked Spectrum (GPS) quasar OQ172 (J1445+0958) has been performed at 1.6, 2.2, 4.8, 8.3 and 15.3 GHz in 2005. Core-jet structures are detected in all bands…

Astrophysics of Galaxies · Physics 2017-05-03 Yi Liu , D. R. Jiang , Minfeng Gu , L. I. Gurvits

Multifrequency polarimetry with the VLBA confirms the previously reported time-varying Faraday rotation measure (RM) in the quasar 3C-279. Variability in the RM and electric vector position angle (EVPA) of the jet component (C4) is seen…

Astrophysics · Physics 2009-11-06 R. T. Zavala , G. B. Taylor

We study the linear polarization of the radio cores of eight blazars simultaneously at 22, 43, and 86 GHz with observations obtained by the Korean VLBI Network (KVN) in three epochs between late 2016 and early 2017 in the frame of the…

We report results from a deep polarization imaging of the nearby radio galaxy 3C$\,$84 (NGC$\,$1275). The source was observed with the Global Millimeter VLBI Array (GMVA) at 86$\,$GHz at an ultra-high angular resolution of $50\mu$as…

The existence of a gradient in the Faraday rotation measure (RM) of the quasar 3C 273 jet is confirmed by follow-up observations. A gradient transverse to the jet axis is seen for more than 20 mas in projected distance. Taking account of…

Astrophysics · Physics 2010-11-11 Keiichi Asada , Makoto Inoue , Seiji Kameno , Hiroshi Nagai

High resolution studies of circular polarization allow us see where it arises in a jet, study its local fractional level and spectrum, and compare these results to local measures of linear polarization and Faraday rotation. Here we not only…

Astrophysics · Physics 2009-11-07 Daniel C. Homan , John F. C. Wardle
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