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Related papers: Kinematics of AGN and Quasar Jets

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The energy budget of all known optical jets is discussed. It is found that to power the extended radio lobes of radio galaxies, the jet bulk motion on kpc scales must be relativistic, on average. Based on various constraints, a ``most…

Astrophysics · Physics 2009-10-31 Riccardo Scarpa , C. Megan Urry

We report that active galactic nucleus (AGN) jets are causally connected on parsec scales, based on 15 GHz Very Long Baseline Array (VLBA) data from a sample of 133 AGN jets. This result is achieved through a new method for measuring the…

High Energy Astrophysical Phenomena · Physics 2014-01-28 E. Clausen-Brown , T. Savolainen , A. B. Pushkarev , Y. Y. Kovalev , J. A. Zensus

Allowing for the conical shape of ultrarelativistic blazar jets with opening angles of a few degrees on parsec-scales we show that their bulk Lorentz factors and viewing angles can be much larger than the values usually inferred by…

Astrophysics · Physics 2009-11-11 Gopal-Krishna , Paul J. Wiita , Samir Dhurde

We probe the role that the directional asymmetry, between relativistic outflows and kilo-parsec scale jets, play in the acceleration of cosmic rays. For this reason we use two powerful, nearby Active Galactic Nuclei (AGNs). These radio…

High Energy Astrophysical Phenomena · Physics 2012-09-06 Nectaria A. B. Gizani

We study the jet kinematics of the blazar S5 0716+714 during its active state in 2003-2004 with multi-epoch VLBI observations. Aims. We present a kinematic analysis of the large-scale (0-12 mas) jet of 0716+714, based on the results of six…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Elizaveta A. Rastorgueva , Kaj J. Wiik , Anisa T. Bajkova , Esko Valtaoja , Leo O. Takalo , Yliya N. Vetukhnovskaya , Mehreen Mahmud

Despite their different nature and physics, blazars and gamma-ray bursts have in common very powerful relativistic jets, which make them the most luminous sources in the Universe. The energy extraction from the central compact object, the…

High Energy Astrophysical Phenomena · Physics 2015-12-15 Elena Pian

VLBI observations of relativistic outflows (jets) in galactic nuclei, complemented with detailed studies made in other spectral domains, have become an effective tool for investigating the physics of nuclear regions in galaxies.…

Astrophysics · Physics 2007-09-03 Andrei Lobanov

We investigate how the angular structure of GRB jets effects the afterglow light curves at different viewing angles, $\theta_{v}$, from the jet symmetry axis. A numerical hydrodynamical modeling for the evolution of a relativistic…

Astrophysics · Physics 2007-05-23 Jonathan Granot , Pawan Kumar , Tsvi Piran

We used 15 GHz VLBA observations of 366 sources having at least 5 epochs within a time interval 1995-2013 from the MOJAVE program and/or its predecessor, the 2 cm VLBA Survey. For each source we produced a corresponding stacked image…

High Energy Astrophysical Phenomena · Physics 2015-02-03 Alexander B. Pushkarev , Matthew L. Lister , Yuri Y. Kovalev , Tuomas Savolainen

We have used the VLBA at 15 GHz to image the structure of 132 strong compact AGN and quasars with a resolution better than one milliarcsecond and a dynamic range typically exceeding 1000 to 1. These observations were made as part of a…

Astrophysics · Physics 2009-10-30 K. I. Kellermann , R. C. Vermeulen , J. A. Zensus , M. H. Cohen

Blazars are thought to possess a relativistic jet that is pointing toward the direction of the Earth and the elect of relativistic beaming enhances its apparent brightness. They radiate in all wavebands from the radio to the gamma-ray bands…

High Energy Astrophysical Phenomena · Physics 2015-02-11 Ryosuke Itoh , Yasushi FUkazawa , Yasuyuki T. Tanaka , Makoto Uemura , Koji S. Kawabata , Hiroshi Akitaya , Kenji Kawaguchi , Yuka Kanda

The $\gamma$-ray bright blazar CTA 102 is studied using imaging (new 15 GHz and archival 43 GHz Very Long Baseline Array, VLBA data) and time variable optical flux density, polarization degree and electric vector position angle (EVPA)…

High Energy Astrophysical Phenomena · Physics 2018-02-21 Xiaofeng Li , P. Mohan , T. An , Xiaoyu Hong , Xiaopeng Cheng , Jun Yang , Yingkang Zhang , Zhongli Zhang , Wei Zhao

We present a kinematic analysis of jet component motion in the VLBI jet of the BL Lac object S5 1803+784, which does not reveal long-term outward motion for most of the components. Understanding the complex kinematic phenomena can possibly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. Britzen , N. A. Kudryavtseva , A. Witzel , R. M. Campbell , E. Ros , M. Karouzos , A. Mehta , M. F. Aller , H. D. Aller , T. Beckert , J. A. Zensus

Parsec-scale VLBA images of BL Lac at 15 GHz show that the jet contains a permanent quasi-stationary emission feature 0.26 mas (0.34 pc projected) from the core, along with numerous moving features. In projection, the tracks of the moving…

High Energy Astrophysical Phenomena · Physics 2014-05-19 M. H. Cohen , D. L. Meier , T. G. Arshakian , D. C. Homan , T. Hovatta , Y. Y. Kovalev , M. L. Lister , A. B. Pushkarev , J. L. Richards , T. Savolainen

Leading models for the "central engine" of long, soft gamma-ray bursts (GRBs) are briefly reviewed with emphasis on the collapsar model. Growing evidence supports the hypothesis that GRBs are a supernova-like phenomenon occurring in star…

Astrophysics · Physics 2009-11-07 S. E. Woosley , W. Zhang , A. Heger

We propose that gamma-ray burst pulses are produced when highly-relativistic jets sweep across an observer's line-of-sight. We hypothesize that axisymmetric jet profiles, coupled with special relativistic effects, produce the time-reversed…

High Energy Astrophysical Phenomena · Physics 2024-03-19 Jon Hakkila , Geoffrey N. Pendleton , Robert D. Preece , Timothy W. Giblin

Relativistic jets of active galactic nuclei have been known to exist for 100 years. Blazars with their jet pointing close to our line of sight are some of the most variable and extreme objects in the universe, showing emission from radio to…

High Energy Astrophysical Phenomena · Physics 2020-08-18 Talvikki Hovatta , Elina Lindfors

We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Akira Mizuta , Kunihito Ioka

Jetted plasma outflows from active galactic nuclei (AGN) represent the most energetic phenomena in the known universe, and play a key role in regulating galaxy formation through feedback processes. The JVLA and VLBA have played an…

Astrophysics of Galaxies · Physics 2018-10-18 Matthew L. Lister , Kenneth I. Kellermann , Preeti Kharb
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