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相关论文: Apparent parsec-scale jet opening angles and \gamm…

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We have investigated the differences in apparent opening angles between the parsec-scale jets of the active galactic nuclei (AGN) detected by the Fermi Large Area Telescope (LAT) during its first three months of operations and those of…

宇宙学与河外天体物理 · 物理学 2009-11-20 A. B. Pushkarev , Y. Y. Kovalev , M. L. Lister , T. Savolainen

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…

高能天体物理现象 · 物理学 2015-02-03 Alexander B. Pushkarev , Matthew L. Lister , Yuri Y. Kovalev , Tuomas Savolainen

We present 15 GHz stacked VLBA images of 373 jets associated with active galactic nuclei (AGN) having at least five observing epochs within a 20 yr time interval 1994-2015 from the MOJAVE programme and/or its precursor, the 2 cm VLBA…

高能天体物理现象 · 物理学 2017-05-09 A. B. Pushkarev , Y. Y. Kovalev , M. L. Lister , T. Savolainen

In its first three months of operations, the Fermi Gamma-Ray Observatory has detected approximately one quarter of the radio-flux-limited MOJAVE sample of bright flat-spectrum active galactic nuclei (AGNs) at energies above 100 MeV. We have…

星系天体物理 · 物理学 2011-02-11 M. L. Lister , D. C. Homan , M. Kadler , K. I. Kellermann , Y. Y. Kovalev , E. Ros , T. Savolainen , J. A. Zensus

We perform a multi-band statistical analysis of core-dominated superluminal active galactic nuclei (AGN) detected with Fermi Large Area Telescope (LAT). The detection rate of $\gamma$-ray jets is found to be high for optically bright AGN.…

宇宙学与河外天体物理 · 物理学 2010-06-14 T. G. Arshakian , J. León-Tavares , J. Torrealba , V. H. Chavushyan

We have compared the radio emission from a sample of parsec-scale AGN jets as measured by the VLBA at 15 GHz, with their associated gamma-ray properties that are reported in the Fermi LAT 3-month bright source list. We find in our…

We have analyzed the parsec-scale jet kinematics of 447 bright radio-loud AGN, based on 15 GHz VLBA data obtained between 1994 August 31 and 2019 August 4. We present new total intensity and linear polarization maps obtained between 2017…

高能天体物理现象 · 物理学 2021-12-14 M. L. Lister , D. C. Homan , K. I. Kellermann , Y. Y. Kovalev , A. B. Pushkarev , E. Ros , T. Savolainen

Very long baseline interferometry (VLBI) observations show that some active galactic nuclei (AGN) jets exhibit bending even at parsec scales. The nature of bending is comprehensively analysed only for a small number of individual AGN, and…

高能天体物理现象 · 物理学 2023-10-05 V. A. Makeev , Y. Y. Kovalev , A. B. Pushkarev

We present 1625 new 15 GHz (2 cm) VLBA images of 295 jets associated with active galactic nuclei (AGNs) from the MOJAVE and 2 cm VLBA surveys, spanning observations between 1994 Aug 31 and 2013 Aug 20. For 274 AGNs with at least 5 VLBA…

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 have compared the parsec-scale jet linear polarization properties of the Fermi LAT-detected and non-detected sources in the complete flux-density-limited (MOJAVE-1) sample of highly beamed AGN. Of the 123 MOJAVE sources, 30 were detected…

高能天体物理现象 · 物理学 2010-08-23 T. Hovatta , M. L. Lister , Y. Y. Kovalev , A. B. Pushkarev , T. Savolainen

We present a new method to measure Gamma*theta_j in flux-limited samples of active galactic nuclei (AGN) jets, where Gamma is the bulk Lorentz factor and theta_j is the jet's half-opening angle. The Gamma*theta_j parameter is physically…

高能天体物理现象 · 物理学 2013-01-25 Eric Clausen-Brown , Tuomas Savolainen , Alexander B. Pushkarev , Yuri Y. Kovalev , Matthew L. Lister

We report first results from KVN and VERA Array (KaVA) VLBI observations obtained in the frame of our Plasma-physics of Active Galactic Nuclei (PAGaN) project. We observed eight selected AGN at 22 and 43 GHz in single polarization (LCP)…

The fine-scale structure and the kinematics of relativistic active galactic nuclei (AGN) jets have been studied by very-long-baseline interferometry at very high resolutions since 1998 at 2 cm wavelength for a sample of over a hundred radio…

天体物理学 · 物理学 2014-11-18 Eduardo Ros

We are compiling a new list of gamma-ray jetted active galactic nuclei (AGN), starting from the fourth catalog of point sources of the Fermi Large Area Telescope (LAT). Our aim is to prepare a list of jetted AGN with known redshifts and…

We have performed a very long baseline interferometry (VLBI) survey of local (z < 0.05) ultra hard X-ray (14-195 keV) selected active galactic nuclei (AGN) from the Swift Burst Alert Telescope (BAT) using KVN, KaVA, and VLBA. We first…

Most extragalactic jets in radio-loud Active Galactic Nuclei are bright and variable gamma-ray sources, which are continuously monitored with Fermi/LAT. We present the gamma-ray properties of the MOJAVE and TANAMI AGN samples of radio-loud…

宇宙学与河外天体物理 · 物理学 2010-06-15 M. Boeck , M. Kadler , G. Tosti , T. H. Burnett , C. Mueller , R. Ojha , J. Wilms

The parsec-scale radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been investigated using observations with the Very Long Baseline Array (VLBA). Comparisons between LAT…

高能天体物理现象 · 物理学 2012-05-04 J. D. Linford , G. B. Taylor , R. W. Romani , J. F. Helmboldt , A. C. S. Readhead , R. Reeves , J. L. Richards

Active galactic nuclei (AGN) with jets seen at small viewing angles are the most luminous and abundant objects in the $\gamma$-ray sky. AGN with jets misaligned along the line-of-sight appear fainter in the sky, but are more numerous than…

高能天体物理现象 · 物理学 2015-06-15 M. Di Mauro , F. Calore , F. Donato , M. Ajello , L. Latronico

We report the detection of a gamma-ray spectral line at approximately 1.5 GeV in three active galactic nuclei (AGN) using 17 years of Fermi-LAT observations. The sample includes both blazars (with relativistic jets directed toward Earth)…

高能天体物理现象 · 物理学 2026-04-02 Shi-Ju Kang , Yue Yin , Yong-Gang Zheng , Qingwen Wu
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