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相关论文: Analysing the Transverse Structure of the Relativi…

200 篇论文

Active Galactic Nuclei (AGN) with bright radio jets offer the opportunity to study the structure of and physical conditions in relativistic outflows. For such studies, multi-frequency polarimetric very long baseline interferometric (VLBI)…

星系天体物理 · 物理学 2015-11-27 Jae-Young Kim , Sascha Trippe , Bong Won Sohn , Junghwan Oh , Jong-Ho Park , Sang-Sung Lee , Taeseok Lee , Daewon Kim

Radio-loud AGN typically manifest powerful relativistic jets extending up to millions of light years and often showing superluminal motions organised in a complex kinematic pattern. A number of physical models are still competing to explain…

高能天体物理现象 · 物理学 2015-05-27 Florent Mertens , Andrei Lobanov

We present first-epoch, milliarcsecond-scale linear polarization images at 15 GHz of 133 jets associated with AGN in the MOJAVE survey (Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments). The sample consists of all known…

天体物理学 · 物理学 2009-09-29 M. L. Lister , D. C. Homan

Polarization has proved an invaluable tool for probing magnetic fields in relativistic jets. Maps of the intrinsic polarization vectors have provided the best evidence to date for uniform, toroidally dominated magnetic fields within jets.…

高能天体物理现象 · 物理学 2015-05-14 Avery E Broderick , Abraham Loeb

We study the kinematics of ridge lines on the pc-scale jet of the active galactic nucleus BL Lac. We show that the ridge lines display transverse patterns that move superluminally downstream, and that the moving patterns are analogous to…

In extragalactic jets, the apparent position of the bright/narrow end (the core) depends on the observing frequency, owing to synchrotron self-absorption and external absorption. The effect must be taken into account in order to achieve…

星系天体物理 · 物理学 2009-04-17 Y. Y. Kovalev , A. B. Pushkarev , A. P. Lobanov , K. V. Sokolovsky

We present a new centimeter polarimetric VLBI image of the BL Lac object 0735+178. This source exhibits one of the most pronounced curvatures observed in jets of AGNs, with two sharp apparent bends of 90 degrees within the inner 2…

天体物理学 · 物理学 2007-05-23 I. Agudo , J. L. Gomez , D. C. Gabuzda , J. C. Guirado , A. Alberdi , A. P. Marscher , M. A. Aloy , J. M. Marti

We present an investigation of the compact structure of the AGN 2021+317 based on multi-epoch Very Long Baseline Interferometry (VLBI) observations at 15, 22, and 43 GHz in the period from 2013 through 2024. The VLBI images show a core-jet…

高能天体物理现象 · 物理学 2025-07-08 Haitian Shang , Wei Zhao , Xiaoyu Hong , Leonid I. Gurvits , Ailing Zeng , Tao An , Xiaopeng Cheng

Active galactic nuclei (AGN) show a range of morphologies and dynamical properties, which are determined not only by parameters intrinsic to the central engine but also their interaction with the surrounding environment. We investigate the…

高能天体物理现象 · 物理学 2022-08-16 Soham Mandal , Paul C. Duffell , Yuan Li

In the current paradigm, it is believed that the compact VLBI radio core of radio-loud AGNs represents the innermost upstream regions of relativistic outflows. These regions of AGN jets have generally been modeled by a conical outflow with…

高能天体物理现象 · 物理学 2017-01-11 Juan-Carlos Algaba , Masanori Nakamura , Keiichi Asada , Sang-Sung Lee

One possible origin for polarization structures across jets of Active Galactic Nuclei (AGNs) with a central "spine" of orthogonal magnetic field and a "sheath" of longitudinal magnetic field along one or both edges of the jet is the…

星系天体物理 · 物理学 2015-06-23 Denise C. Gabuzda , Andrea Reichstein , Eamonn L. O'Neill

We developed the full magnetohydrodynamical analytical jet model that allows accurate reproducing of a transversal and longitudinal structure for a highly collimated relativistic jets. This model can be used as a setup for convenient…

高能天体物理现象 · 物理学 2025-10-29 E. E. Nokhrina , I. N. Pashchenko , V. A. Frolova , R. V. Todorov

Multi-frequency VLBI observations allow studies of the continuum spectrum in the different parts of the parsec scale jets of AGN, providing information on the physical properties of the plasma and magnetic fields in them. Since VLBI…

天体物理学 · 物理学 2009-04-14 T. Savolainen , K. Wiik , E. Valtaoja , M. Tornikoski

In this paper we describe a new approach for mm-VLBI calibration that provides bona-fide astrometric alignment of the mm-wavelength images from a single source, for the measurement of frequency dependent effects, such as `core-shifts' near…

天体物理仪器与方法 · 物理学 2017-01-18 Richard Dodson , María Rioja , Sol Molina , José-Luis Gómez

Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key science objectives of the RadioAstron space-VLBI mission.…

星系天体物理 · 物理学 2020-01-10 Gabriele Bruni , Tuomas Savolainen , Jose Luis Gómez , Andrei P. Lobanov , Yuri Y. Kovalev

In the current paradigm, it is believed that the compact VLBI radio core of radio-loud active galactic nuclei (AGNi) represents the innermost upstream regions of relativistic outflows. These regions of AGN jets have generally been modeled…

星系天体物理 · 物理学 2019-05-17 Juan Carlos Algaba , Masanori Nakamura , Keiichi Asada , Sang Sung Lee

Observational studies of collimation in jets in active galactic nuclei (AGN) are a key to understanding their formation and acceleration processes. We have performed an automated search for jet shape transitions in a sample of 367 AGN using…

The formation of relativistic jets in active galactic nuclei (AGN) is related to accretion on to their central supermassive black holes, and magnetic fields are believed to play a central role in launching, collimating and accelerating the…

星系天体物理 · 物理学 2017-02-23 Juliana C. Motter , Denise C. Gabuzda

Using stacking of images obtained at different epochs, we studied the variability properties of linear polarization of active galactic nucleus (AGN) jets on parsec-scales. Our sample is drawn from the MOJAVE programme, and consists of 436…

Accurate measurement of the frequency-dependent shift of the self-absorbed radio core is required for multi-frequency analysis of VLBI data since absolute positional information is lost as a result of phase self-calibration. We use the…

天体物理学 · 物理学 2008-12-19 Shane P. O'Sullivan , Denise C. Gabuzda