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相关论文: Magnetic Field Structures In and Around Seyfert Ga…

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Our understanding of the unification of jetted AGNs has advanced greatly as the size of extragalactic sources increased. In the present paper, based on the large sample of radio sources, we compiled 680 blazars (279 FSRQs and 401 BL Lacs)…

星系天体物理 · 物理学 2021-11-17 E. U. Iyida , I. O. Eya , F. C. Odo

We present ROSAT PSPC and HRI images of eight galaxies selected from a distance-limited sample of 22 edge-on Seyfert galaxies. Kiloparsec-scale soft X-ray nebulae extend along the galaxy minor axes in three galaxies (NGC 2992, NGC 4388 and…

天体物理学 · 物理学 2009-10-30 Edward J. M. Colbert , Stefi A. Baum , Chris P. O'Dea , Sylvain Veilleux

The Very Large Array has been used at five frequencies to study the structure and linear polarization of SS433 on scales as small as ~0.1" ~ 500 AU. Each jet consists of a sharp, curving ridge-line at the leading edge, plus significant…

天体物理学 · 物理学 2009-11-13 David H. Roberts , John F. C. Wardle , Scott L. Lipnick , Philip L. Selesnick , Simon Slutsky

We present the results of high resolution VLBI observations at 1.6 and 4.9 GHz of the radio-loud Seyfert galaxy, Mrk 6. These observations are able to detect a compact radio core in this galaxy for the first time. The core has an inverted…

星系天体物理 · 物理学 2015-06-18 P. Kharb , C. P. O'Dea , S. A. Baum , M. J. Hardcastle , D. Dicken , J. H. Croston , B. Mingo , J. Noel-Storr

We present models of the H$\beta$-emitting broad-line region (BLR) in seven Seyfert 1 galaxies from the Lick AGN (Active Galactic Nucleus) Monitoring Project 2011 sample, drawing inferences on the BLR structure and dynamics as well as the…

In the past decade, high sensitivity radio surveys have revealed that the local radio AGN population is dominated by moderate-to-low power sources with emission that is compact on galaxy scales. High-excitation radio galaxies (HERGs) with…

星系天体物理 · 物理学 2020-03-04 Jonathon C. S. Pierce , Clive N. Tadhunter , Raffaella Morganti

The Gigahertz Peaked Spectrum (GPS) sources, Compact Steep Spectrum (CSS) radio sources, and High Frequency Peakers (HFP) radio sources are thought to be young radio AGNs, at the early stage of AGN evolution. We investigated the optical…

星系天体物理 · 物理学 2019-12-11 Mai Liao , Minfeng Gu

We present the results from 685 MHz observations with the upgraded Giant Metrewave Radio Telescope (uGMRT) of 22 quasars belonging to the Palomar-Green (PG) quasar sample. Only four sources reveal extended radio structures on $\sim$10-30…

星系天体物理 · 物理学 2020-12-22 Silpa S. , P. Kharb , L. C. Ho , C. H. Ishwara-Chandra , M. E. Jarvis , C. Harrison

High-energy {\gamma}-rays, which are produced by powerful relativistic jets, are usually associated with blazars and radio galaxies. In the current active galactic nuclei (AGN) paradigm, such jets are almost exclusively launched from…

星系天体物理 · 物理学 2014-12-24 Emilia Järvelä , Anne Lähteenmäki , Jonathan León-Tavares

We present 6 GHz e-MERLIN observations of 42 $z<0.2$ type 1 and type 2 mostly radio-quiet quasars ($L_{\rm[OIII]}\gtrsim10^{42}$ erg s$^{-1}$; $L_{\rm AGN}\gtrsim10^{45}$ erg s$^{-1}$) from the Quasar Feedback Survey. The nature and origin…

Low-luminosity AGNs are perceived to be radio loud and devoid of a ``big blue bump'', indicating a transition from a radiatively efficient, geometrically thin, accretion disc in high-luminosity AGNs, to a geometrically thick, radiatively…

天体物理学 · 物理学 2008-11-26 Dan Maoz

We report on the study of an intriguing active galaxy that was selected as a potential multiple supermassive black hole merger in the early-type host SDSS J151709.20+335324.7 (z=0.135). Ground-based SDSS imaging reveals two blue structures…

宇宙学与河外天体物理 · 物理学 2015-05-18 D. J. Rosario , G. A. Shields , G. B. Taylor , S. Salviander , K. L. Smith

We present the results of the analysis of a sample of 17 low-luminosity (L_x < 1e42 erg/s), radio loud AGNs in massive galaxies. The sample is extracted from the SDSS database and it spans uniformly a wide range in optical [OIII] emission…

宇宙学与河外天体物理 · 物理学 2015-05-27 F. de Gasperin , A. Merloni , P. Sell , P. Best , S. Heinz , G. Kauffmann

We present the first results of a radio survey of 79 narrow-line Seyfert 1 (NLS1) carried out with the Karl G. Jansky Very Large Array (JVLA) at 5 GHz in A configuration aimed at studying the radio properties of these sources. We report the…

The magnetic field structure in GRB outflows is of great interest as it can provide valuable clues that can help pin down the mechanism responsible for the acceleration and collimation of GRB jets. The most promising way of probing it is…

天体物理学 · 物理学 2009-11-10 Jonathan Granot , Gregory B. Taylor

We have launched a search for large-scale ($\gapprox$1 kpc) minor-axis outflows in edge-on Seyfert galaxies in order to assess their frequency of occurrence and study their properties. Here we present optical continuum and \han2 line images…

We methodically model the broad-band Suzaku spectra of a small sample of six 'bare' Seyfert galaxies: Ark 120, Fairall 9, MCG-02-14-009, Mrk 335, NGC 7469 and SWIFT J2127.4+5654. The analysis of bare Seyferts allows a consistent and…

高能天体物理现象 · 物理学 2015-05-20 A. R. Patrick , J. N. Reeves , D. Porquet , A. G. Markowitz , A. P. Lobban , Y. Terashima

Narrow-line Seyfert 1 galaxies (NLS1s) are active galactic nuclei (AGN) recently identified as a new class of $\gamma$-ray sources. The high energy emission is explained by the presence of a relativistic jet observed at small angles, just…

We present a new accurate catalog of narrow-line Seyfert 1 galaxies (NLS1s) in the southern hemisphere from the Six-degree Field Galaxy Survey (6dFGS) final data release, which is currently the most extensive spectroscopic survey available…

星系天体物理 · 物理学 2018-09-14 S. Chen , M. Berton , G. La Mura , E. Congiu , V. Cracco , L. Foschini , J. H. Fan , S. Ciroi , P. Rafanelli , D. Bastieri

AGN feedback is a well known mechanism in the evolution of galaxies. One open question is the driving mechanism of galaxy-scale outflows. At low redshift, radio jets often interact with the ISM, generating turbulence and driving ionized…