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[abridged] We report on Suzaku observations of selected regions within the Southern giant lobe of the radio galaxy Centaurus A. We focus on distinct X-ray features likely associated with fine radio structure of the lobe. We find that the…

Previous research showed most BL Lac objects and some quasars have aligned VLBI-core and optical polarizations, although some of the AGNs also showed no obvious relationship between VLBI-core and optical polarization angles. This may…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 J. C. Algaba , D. C. Gabuzda , P. S. Smith

We present new radio observations of 9 members of a sample of 29 nearby (z < 0.2) BL Lac objects. The new data have been obtained with the European VLBI Network and/or the MERLIN at 1.6 and 5 GHz and complement previous observations. For…

Astrophysics · Physics 2008-11-26 M. Giroletti , G. Giovannini , G. B. Taylor , R. Falomo

Radio galaxies harbouring jetted active galactic nuclei are a frequent target of very-long-baseline interferometry (VLBI) because they play an essential role in exploring how jets form and propagate. Hence, only few have not been detected…

We report the systematic analysis of knots, hotspots, and lobes in 57 active galactic nuclei (AGNs) to investigate the variation of the magnetic field along with the jet from the sub-pc base to the terminus in kpc-to-Mpc scales. Expanding…

Astrophysics of Galaxies · Physics 2021-08-11 Soichiro Ito , Yoshiyuki Inoue , Jun Kataoka

We present an analysis of archival multi-frequency Very Large Array monitoring data of the two-image gravitational lens system CLASS B1600+434, including the polarization properties at 8.5 GHz. From simulating radio light curves…

Astrophysics of Galaxies · Physics 2021-07-07 A. D. Biggs

New radio data at 330 MHz are presented for the rich clusters Abell 665 and Abell 2163, whose radio emission is characterized by the presence of a radio halo. These images allowed us to derive the spectral properties of the two clusters…

Astrophysics · Physics 2009-11-10 L. Feretti , E. Orru' , G. Brunetti , G. Giovannini , N. Kassim , G. Setti

We present for the first time Very-Long-Baseline Interferometry images of the radio galaxy Cygnus A at the frequency of $86$ $\rm GHz$. Thanks to the high spatial resolution of only ${\sim}200$ Schwarzschild radii ($R_{\bf S}$), such…

High Energy Astrophysical Phenomena · Physics 2016-03-30 B. Boccardi , T. P. Krichbaum , U. Bach , M. Bremer , J. A. Zensus

We propose a morphological classification based on the parsec scale structure of fifty-one High Frequency Peakers (HFPs) from the ``bright'' HFP sample. VLBA images at two adjacent frequencies (chosen among 8.4, 15.3, 22.2 and 43.2 GHz)…

Astrophysics · Physics 2009-11-11 M. Orienti , D. Dallacasa , S. Tinti , C. Stanghellini

The VLA-COSMOS large project is described and its scientific objective is discussed. We present a catalog of ~ 3,600 radio sources found in the 2deg^2 COSMOS field at 1.4 GHz. The observations in the VLA A and C configuration resulted in a…

We propose a jet model for the low/hard state of Galactic black-hole X-ray sources that can explain the energy spectra from radio to X-rays. The model assumes that i) there is a magnetic field along the axis of the jet; ii) the electron…

Astrophysics · Physics 2009-11-10 Dimitrios Giannios

Eighteen days of MERLIN data and 42 hours of A-array VLA data at 1.4 GHz have been combined to image a 10-arcmin field centred on the Hubble Deep and Flanking Fields (HDF and HFF). A complete sample of 92 radio sources with 1.4-GHz flux…

Supermassive black holes at the centre of active galactic nuclei power some of the most luminous objects in the Universe. Typically, very long baseline interferometric (VLBI) observations of blazars have revealed only funnel-like…

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…

Astrophysics of Galaxies · Physics 2009-04-17 Y. Y. Kovalev , A. B. Pushkarev , A. P. Lobanov , K. V. Sokolovsky

We present results from the highest resolution polarization imaging survey of a complete sample of extragalactic radio sources carried out to date. Our sample consists of a statistically complete flat-spectrum subset of 32 AGNs from the…

Astrophysics · Physics 2009-11-07 Matthew L. Lister

We present observations made with the VLA at 1.5 and 8.4 GHz of the nearby FRI radio galaxy 3C296. The most recent models of FRI radio galaxies suggest that substantial deceleration must take place in their jets, with strongly relativistic…

Astrophysics · Physics 2016-01-13 M. J. Hardcastle , P. Alexander , G. G. Pooley , J. M. Riley

We analyze radio continuum and line observations from the archives of the Very Large Array, as well as X-ray observations from the \emph{Chandra} archive of the region of massive star formation W75N. Five radio continuum sources are…

Solar and Stellar Astrophysics · Physics 2015-05-18 C. Carrasco-Gonzalez , L. F. Rodriguez , J. M. Torrelles , G. Anglada , O. Gonzalez-Martin

We present new VLA, MERLIN and VLBI images for the radio galaxy 3C 338, and the results of the monitoring of its arcsecond core flux density. Present high sensitivity observations allow us to investigate the radio structure of this source…

Astrophysics · Physics 2009-10-30 G. Giovannini , W. D. Cotton , L. Feretti , L. Lara , T. Venturi

We present multifrequency radio continuum as well as HI observations of the superwind galaxy NGC1482, with both the GMRT and the VLA. This galaxy has a remarkable hourglass-shaped optical emission line outflow as well as bi-polar soft X-ray…

Astrophysics · Physics 2009-11-10 Ananda Hota , D. J. Saikia