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Related papers: Optical polarization properties of AGN with signif…

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We present a sample of 18 optically-selected and X-ray detected spatially offset active galactic nuclei (AGN) from the Sloan Digital Sky Survey (SDSS). In 9 systems, the X-ray AGN is spatially offset from the galactic stellar core that is…

Astrophysics of Galaxies · Physics 2016-09-28 R. Scott Barrows , Julia M. Comerford , Jenny E. Greene , David Pooley

In most of Seyfert-1 active galactic nucei (AGN) the optical linear continuum polarization degree is usually small (less than 1%) and the polarization position angle is nearly parallel to the AGN radio-axis. However, there are many types-1…

Astrophysics of Galaxies · Physics 2017-02-22 N. A. Silant'ev , Yu. N. Gnedin , M. Yu. Piotrovich , T. M. Natsvlishvili , S. D. Buliga

Relativistic jets are collimated outflows with speeds close to light speed, which are associated with gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and so on. This article mainly overviews recent developments of polarimetric…

High Energy Astrophysical Phenomena · Physics 2021-12-28 Kenji Toma

Over the past few decades, our knowledge of jets produced by active galactic nuclei (AGN) has greatly progressed thanks to the development of very-long-baseline interferometry (VLBI). Nevertheless, the crucial mechanisms involved in the…

High Energy Astrophysical Phenomena · Physics 2017-11-22 B. Boccardi , T. P. Krichbaum , E. Ros , J. A. Zensus

Short millimeter observations of radio-loud AGN offer the opportunity to study the physics of their inner relativistic jets, from where the bulk millimeter emission is radiated. Millimeter jets are significantly less affected by Faraday…

Astrophysics of Galaxies · Physics 2014-07-02 I. Agudo , C. Thum , J. L. Gomez , H. Wiesemeyer

In order to identify the dominant nuclear outflow mechanisms in Active Galactic Nuclei, we have undertaken deep, high resolution observations of two compact radio sources (PKS 1549-79 and PKS 1345+12) with the Advanced Camera for Surveys…

Aims: The effect of frequency-dependent AGN core positions (``core-shifts'') on radio Very Long Baseline Interferometry (VLBI) global astrometry measurements is investigated. Methods: The basic equations relating to VLBI astrometry are…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. W. Porcas

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

Radio-loud active galactic nuclei (AGNs), hosting powerful relativistic jet outflows, provide an excellent laboratory for studying jet physics. Very long baseline interferometry (VLBI) enables high-resolution imaging on milli-arcsecond…

High Energy Astrophysical Phenomena · Physics 2018-02-07 X. -P. Cheng , T. An , X. -Y. Hong , J. Yang , P. Mohan , K. I. Kellermann , M. L. Lister , S. Frey , W. Zhao , Z. -L. Zhang , X. -C. Wu , X. -F. Li , Y. -K. Zhang

We have measured the angular sizes of radio cores of active galactic nuclei (AGN) and analyzed their sky distributions and frequency dependencies to study synchrotron opacity in AGN jets and the strength of angular broadening in the…

High Energy Astrophysical Phenomena · Physics 2017-05-31 A. B. Pushkarev , Y. Y. Kovalev

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

High redshift active galactic nuclei (AGN) provide key insights into early supermassive black hole growth and cosmic evolution. This study investigates the parsec-scale properties of 86 radio-loud quasars at z $\geq$ 3 using very long…

High Energy Astrophysical Phenomena · Physics 2025-02-24 Shaoguang Guo , Tao An , Yuanqi Liu , Chuanzeng Liu , Zhijun Xu , Yulia Sotnikova , Timur Mufakharov , Ailing Wang

We investigate apparent internal structure of kiloparsec scale jets of AGNs arising from the energy dependent cooling of accelerated electrons and light travel time effect for relativistically moving sources. Using a simple cylindrical…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-20 M. G. Kim , F. Takahara

While 2% of active galactic nuclei (AGNs) exhibit narrow emission lines with line-of-sight velocities that are significantly offset from the velocity of the host galaxy's stars, the nature of these velocity offsets is unknown. We…

Astrophysics of Galaxies · Physics 2017-10-04 Julia M. Comerford , R. Scott Barrows , Jenny E. Greene , David Pooley

We extend previous works by considering two additional radio frequencies (K band and X/Ka band) with the aim to study the frequency dependence of the source positions and its potential connection with the physical properties of the…

Instrumentation and Methods for Astrophysics · Physics 2021-08-18 Niu Liu , Sebastien Lambert , Patrick Charlot , Zi Zhu , Jia-Cheng Liu , Nan Jiang , Xiao-Sheng Wan , Cheng-Yu Ding

We have analyzed the differences in positions of 9081 matched sources between the Gaia DR2 and VLBI catalogues. The median position uncertainty of matched sources in the VLBI catalogue is a factor of two larger than the median position…

Astrophysics of Galaxies · Physics 2018-11-20 L. Petrov , Y. Y. Kovalev , A. V. Plavin

We analyze the linear polarization of the relativistic jet in BL Lacertae object OJ~287 as revealed by multi-epoch Very Long Baseline Array (VLBA) images at 43 GHz and monitoring observations at optical bands. The electric-vector position…

We present the results of a multi-frequency, multi-scale radio polarimetric study with the Very Large Array (VLA) of the Seyfert 1 galaxy and BALQSO, Mrk 231. We detect complex total and polarized intensity features in the source. Overall,…

Astrophysics of Galaxies · Physics 2021-11-16 Silpa S. , P. Kharb , C. P. O' Dea , S. A. Baum , B. Sebastian , D. Mukherjee , C. M. Harrison

(See the complete and formatted abstract in the paper). We report on VLBI monitoring of the low-luminosity AGN (LLAGN) in M81 at 1.7, 2.3, 5, and 8.4GHz. These observations are phase-referenced to the supernova SN1993J (located in the same…

High Energy Astrophysical Phenomena · Physics 2015-05-28 I. Marti-Vidal , J. M. Marcaide , A. Alberdi , M. A. Perez-Torres , E. Ros , J. C. Guirado

Gaia will open up a huge volume of new parameter space in which to explore the physics of AGN and black hole evolution. We address the question as to how far along the relativistic jets blazar radio, optical and gamma ray emission…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-30 Ian Browne
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