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Related papers: Variability and parsec-scale radio structure of ca…

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We present preliminary results from a statistical survey of compact structure in faint radio sources. Around 1000 sources from the VLA FIRST survey (flux densities larger than 1 mJy at 1.4 GHz) have been observed with the single-baseline…

Astrophysics · Physics 2007-05-23 R. W. Porcas , W. Alef , T. Ghosh , C. J. Salter , S. T. Garrington

We present a census of sub-pc scale properties of the VLBI cores in a complete sample of local Seyfert galaxies. Seventeen out of 23 sources with a VLA detection are detected also with VLBI at 1.7 GHz and/or 5 GHz, with an average…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Francesca Panessa , Marcello Giroletti

We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarization of the complete sample and a list of additional GPS…

Astrophysics · Physics 2016-08-30 C. Stanghellini , C. P. O'Dea , D. Dallacasa , S. A. Baum , R. Fanti , C. Fanti

We performed high resolution radio observations of a new sample of ten BAL quasars using both the VLBA and EVN at 5 GHz. All the selected sources have balnicity indices (BI) more than 0 and radio flux densities less than 80 mJy at 1.4 GHz.…

Astrophysics of Galaxies · Physics 2015-07-15 M. Kunert-Bajraszewska , M. Ceglowski , K. Katarzynski , C. Roskowinski

Recently a population of compact radio galaxies were classified as Fanaroff-Riley type 0 radio galaxies (FR 0s). The physical nature of FR 0s and the connection with the classical FR I and II galaxies are not currently well understood.…

High Energy Astrophysical Phenomena · Physics 2018-08-29 X. -P. Cheng , T. An

We present results from a multi-epoch Very Long Baseline Array (VLBA) survey conducted as part of the DYNAMO-VLBA project, aimed at measuring the dynamical masses of young stellar systems in the Orion complex. Our observations include 19…

We present Karl G. Janksy Very Large Array (VLA) 1.3 cm, 3.6 cm, and 6 cm continuum maps of compact radio sources in the Orion Nebular Cluster. We mosaicked 34 square arcminutes at 1.3 cm, 70 square arcminutes at 3.6 cm and 109 square…

Astrophysics of Galaxies · Physics 2016-11-15 Patrick D. Sheehan , Josh A. Eisner , Rita K. Mann , Jonathan P. Williams

In almost 30 years of operation, the Very Large Array (VLA) has proved to be a remarkably flexible and productive radio telescope. However, the basic capabilities of the VLA have changed little since it was designed. A major expansion…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. Perley , P. Napier , J. Jackson , B. Butler , B. Carlson , D. Fort , P. Dewdney , B. Clark , R. Hayward , S. Durand , M. Revnell , M. McKinnon

We have re-examined an ancient VLBI survey of ultra-comact radio sources at 2.29 GHz, which gave fringe amplitudes for 917 such objects with total flux density >0.5 Jy approximately. A number of cosmological investigations based upon this…

Astrophysics · Physics 2009-11-11 J C Jackson , A L Jannetta

We have selected a sample of 80 candidates for obscured radio-loud active galactic nuclei and presented their basic optical/near-infrared (NIR) properties in Paper 1. In this paper, we present both high-resolution radio continuum images for…

Astrophysics of Galaxies · Physics 2016-03-16 Ting Yan , John T. Stocke , Jeremy Darling , Emmanuel Momjian , Soniya Sharma , Nissim Kanekar

We have used the Very Large Array(VLA) in C configuration to carry out a sensitive 20cm radio survey of regions of sky that have been surveyed in the Far Infra-Red over the wavelength range 5-200 microns with ISO as part of the European…

The statistical study of the parsec scale properties of radio sources is crucial to get information on the nature of the central engine and to provide the foundations of the current unified theories, suggesting that the appearance of active…

Astrophysics of Galaxies · Physics 2015-04-14 Elisabetta Liuzzo , Gabriele Giovannini , Marcello Giroletti

Multi-frequency 1.7, 5 and 8.4-GHz VLBA observations of a radio-loud broad absorption line (BAL) quasar 1045+352 are presented. It is a young compact steep spectrum (CSS) object and its asymmetric, two-sided morphology on a scale of several…

Astrophysics · Physics 2008-11-26 Magdalena Kunert-Bajraszewska , Andrzej Marecki

To determine the location of the intra-day variable (IDV) emission region within the jet of the BL Lac object S5 0716+714, a multi-epoch VSOP polarization experiment was performed in Autumn 2000. To detect, image, and monitor the short term…

Astrophysics · Physics 2009-11-11 U. Bach , T. P. Krichbaum , A. Kraus , A. Witzel , J. A. Zensus

We analyze the results of processing of data of observations which had been carried out with the VLBA during 10 last years. All the data have been retrieved from archive of the National Radio Astronomy Observatory (USA NRAO, Socorro, New…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 A. Chuprikov , I. Guirin

We present multi-wavelength radio observations with the Very Large Array and narrow- and broad-band optical observations with the 2.5m telescope at the Las Campanas Observatory, of a well-defined sample of high-luminosity Fanaroff-Riley…

Astrophysics · Physics 2009-10-31 C. H. Ishwara-Chandra , D. J. Saikia , P. J. McCarthy , W. J. M. van Breugel

We present a catalogue of positions and correlated flux densities of 410 flat-spectrum, compact extragalactic radio sources, previously detected in the AT20G survey. The catalogue spans the declination range -90deg, -40deg and was…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-24 Leonid Petrov , Chris Phillips , Alessandra Bertarini , Tara Murphy , Elaine M. Sadler

We present the analysis of VLA and VLBA observations of the radio source 3C 338, associated with the cD galaxy NGC 6166, the central dominant galaxy of the cluster Abell 2199. The VLBA observations were done at 8.4 and 15.4 GHz, while the…

Astrophysics · Physics 2011-02-11 G. Gentile , C. Rodriguez , G. B. Taylor , G. Giovannini , S. W. Allen , W. M. Lane , N. E. Kassim

Radio-bright BL Lacertae objects (BLOs) are typically variable and exhibit prominent flaring. We use a sample of 24 BLOs to get a clear idea of their flaring behavior and to find possible commonalities in their variability patterns. Our…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 E. Nieppola , T. Hovatta , M. Tornikoski , E. Valtaoja , M. F. Aller , H. D. Aller

We report preliminary results of a visual inspection of ~4300 deg$^2$ covered by 4414 images of the 3-GHz VLA Sky Survey (VLASS, epoch 1.1) in search of extended radio structures. Over 7600 positions were registered, and for a subset of 270…

Astrophysics of Galaxies · Physics 2018-08-23 Agueda C. Villarreal Hernández , Heinz Andernach
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