English
Related papers

Related papers: Time Variation of Rotation Measure Gradient in 3C …

200 papers

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

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

In this work we interpret and discuss the time variable rotation measure (RM) found, for the first time over a 1-yr period, in the core region of a blazar. These results are based on a one-year, multi-frequency (15, 24, and 43 GHz) Very…

High Energy Astrophysical Phenomena · Physics 2017-10-30 R. Lico , J. L. Gómez , K. Asada , A. Fuentes

Both in the Faraday Rotation Measure and the intrinsic polarization angle, new features are revealed to indicate a helical magnetic field operating along the jet of the bright active galactic nuclei 3C 273. The helical field has been…

We report on multi-frequency polarimetry Very Long Baseline Interferometry observations of active galactic nuclei using the VLBA. These observations are used to construct images of the Faraday Rotation Measure (RM) in J1613+342, Mrk 501, 3C…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. B. Taylor , R. Zavala

Using the numerical data of MHD simulation for AGN jets based on our ``sweeping magnetic twist model'', we calculated the Faraday rotation measure (FRM) and the Stokes parameters to compare with observations. We propose that the FRM…

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

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

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 investigate the distribution of Faraday rotation measure (RM) in the M87 jet at arc-second scales by using archival polarimetric VLA data at 8, 15, 22 and 43 GHz. We resolve the structure of the RM in several knots along the jet for the…

High Energy Astrophysical Phenomena · Physics 2016-06-01 Juan-Carlos Algaba , Keiichi Asada , Masanori Nakamura

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

A monotonic, statistically significant gradient in the observed Faraday Rotation Measure (RM) across the jet of an Active Galactic Nucleus (AGN) reflects a corresponding gradient in the electron density and/or line-of-sight magnetic (B)…

Astrophysics of Galaxies · Physics 2015-11-30 Denise C. Gabuzda , Sebastian Knuettel , Annalisa Bonafede

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

Our modelling of FR I radio jets as decelerating, relativistic flows allows us to derive their orientations accurately. We present images of Faraday rotation for two of these these objects (3C 31 and NGC 315) and show that the fluctuations…

Astrophysics · Physics 2009-11-11 R. A. Laing , J. R. Canvin , W. D. Cotton , A. H. Bridle , P. Parma

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

The results of VLBI observations of the quasar 3C273, obtained during a multi-frequency campaign in late 1992 in the radio, millimeter and X-ray bands are presented and discussed. The VLBI observations were made at 22 GHz with a Global…

Astrophysics · Physics 2007-05-23 F. Mantovani , W. Junor , C. Valerio , I. McHardy

We present new results on the parsec-scale jet of the quasar 3C395, derived from VLBI polarization sensitive observations made in 1995.91 and 1998.50 at 8.4, 15.4 and 22.2 GHz. The observations show a complex one-sided jet extending up to…

Astrophysics · Physics 2009-11-06 L. Lara , A. Alberdi , J. M. Marcaide

We present the results of a parsec-scale polarization study of three FRI radio galaxies - 3C66B, 3C78 and 3C264 - obtained with the Very Long Baseline Array at 5, 8 and 15 GHz. Parsec-scale polarization has been detected in a large number…

Astrophysics of Galaxies · Physics 2011-02-11 P. Kharb , D. C. Gabuzda , C. P. O'Dea , P. Shastri , S. A. Baum

In this paper we comment on the possibility for intermittent jet activity in quasar 3C 273 on different time-scales. We propose, that striking morphology of the large-scale radio jet in this source, as well as the apparent lack of its…

Astrophysics · Physics 2009-11-10 L. Stawarz

We present results from multifrequency polarimetry of NRAO 140 using the Very Long Baseline Array. These observations allow us to reveal the distributions of both the polarization position angle and the Faraday rotation measure (RM). These…

Astrophysics · Physics 2009-11-13 Keiichi Asada , Makoto Inoue , Masanori Nakamura , Seiji Kameno , Hiroshi Nagai

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