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Related papers: Centimeter-band Variability in GPS Sources

200 papers

In the time domain, the radio sky in particular along the Galactic plane direction may vary significantly because of various energetic activities associated with stars, stellar and supermassive black holes. Using multi-epoch Very Large…

High Energy Astrophysical Phenomena · Physics 2022-01-12 Jun Yang , Yongjun Chen , Leonid I. Gurvits , Zsolt Paragi , Aiyuan Yang , Xiaolong Yang , Zhiqiang Shen

(ABRIDGED) We present here the results from new Very Long Baseline Array observations at 1.6 and 5 GHz of 19 galaxies of a complete sample of 21 UGC FRI radio galaxies. New Chandra data of two sources, viz., UGC00408 and UGC08433, are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 P. Kharb , C. O'Dea , A. Tilak , S. Baum , E. Haynes , J. Noel-Storr , C. Fallon , K. Christiansen

Aims: The knowledge of the properties of the youngest radio sources is very important in order to trace the earliest phase of the evolution of the radio emission. RXJ1459+3337, with its high turnover frequency (~25 GHz) provides a unique…

Astrophysics · Physics 2009-11-13 M. Orienti , D. Dallacasa

We observed with the VLBA at 2.3 and 8.6 GHz a complete flux-density limited sample of 482 radio sources with declination >+75 degrees brighter than 200 mJy at 1.4 GHz drawn from the NVSS catalog. 34% of the sources show parsec-scale…

Astrophysics of Galaxies · Physics 2021-02-01 Alexander V. Popkov , Yuri Y. Kovalev , Leonid Y. Petrov , Yuri A. Kovalev

Aims and Methods: We present the results of VLBI observations of nineteen GHz-Peaked-Spectrum (GPS) radio sources at 1.6 GHz. Of them, 15 sources are selected from the Parkes Half Jansky (PHJ) sample (Snellen 2002), 4 others are from our…

Astrophysics · Physics 2007-07-10 Xiang Liu , Lang Cui , Wen-Feng Luo , Wei-Zhao Shi , Hua-Gang Song

Results of multi-frequency VLBA polarization imaging for sources showing evidence of quasi-periodic variations in their total flux density are discussed. Possible origins of the observed behavior are proposed.

Astrophysics · Physics 2007-05-23 T. B. Pyatunina , D. C. Gabuzda , S. G. Jorstad , M. F. Aller , H. D. Aller , H. Terasranta

We report the results of a 5 GHz southern hemisphere VLBI survey of compact extragalactic radio sources. These observations were undertaken with the SHEVE array plus Shanghai station in November 1992. A sample of 22 sources was observed and…

A wide range of phenomena, from explosive transients to active galactic nuclei, exhibit variability at radio wavelengths on timescales of a few years. Characterizing the rate and scale of variability in the radio sky can provide keen…

Astrophysics of Galaxies · Physics 2026-05-21 Yjan A. Gordon , Peter S. Ferguson , Michael N. Martinez , Eric J. Hooper

We present results of EVN observations of eleven GHz-Peaked-Spectrum (GPS) radio sources at 2.3/8.4 GHz. These sources are from the classical ''bright'' GPS source samples with peak flux densities $>$ 0.2 Jy and spectral indices $\alpha <…

Astrophysics · Physics 2007-05-23 L. Xiang , D. Dallacasa , P. Cassaro , D. Jiang , C. Reynolds

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 report on the first results of the POLAMI program, a simultaneous 3.5 and 1.3mm full-Stokes-polarisation monitoring of a sample of 36 of the brightest active galactic nuclei in the northern sky with the IRAM 30m Telescope. Through a…

Astrophysics of Galaxies · Physics 2017-09-27 Ivan Agudo , Clemens Thum , Venkatessh Ramakrishnan , Sol N. Molina , Carolina Casadio , Jose L. Gomez

We report on multi-frequency linear polarization monitoring of 15 active galactic nuclei containing highly relativistic jets with apparent speeds from $\sim$4 $c$ to $>40c$. The measurements were obtained at optical, 1 mm, and 3 mm…

The Caltech-Jodrell Bank VLBI surveys of bright extragalactic radio sources north of declination 35 deg were carried out between 1990 and 1995 using the Mark-II system, achieving images with a resolution of about 1 mas at 5 GHz. The CJ1…

We observed 51 sources in the Q-U-I JOint TEnerife (QUIJOTE) cosmological fields which were brighter than 1 Jy at 30 GHz in the Planck Point Source Catalogue (version 1), with the Very Large Array at 28 -- 40 GHz, in order to characterise…

We interpret the linear polarization structures observed in extragalactic radio sources, even those oriented at oblique angles to the jet flows, to be due to oblique, relativistic shock fronts in the emitting regions. Many sources exhibit…

Astrophysics · Physics 2007-05-23 H. D. Aller , M. F. Aller , P. A. Hughes

We present polarization measurements at 8.4, 22, and 43 GHz made with the VLA of a complete sample of extragalactic sources stronger than 1 Jy in the 5-year WMAP catalogue and with declinations north of -34 degrees. The observations were…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-07 N. Jackson , I. W. A. Browne , R. A. Battye , D. Gabuzda , A. C. Taylor

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 have carried out observations at 18.5 GHz with the Australia Telescope Compact Array (ATCA) of 250 out of the 258 Southern extragalactic sources in the complete 5 GHz 1 Jy sample by K\"uhr et al. (1981). In this paper we focus on the…

Astrophysics · Physics 2009-11-10 R. Ricci , I. Prandoni , C. Gruppioni , R. J. Sault , G. De Zotti

Very recently, J 1128+5925 was found to show strong intraday variability at radio wavelengths and may be a new source with annual modulation of the timescale of its radio variability. Therefore, its radio variability can be best explained…

Astrophysics · Physics 2008-11-26 Jianghua Wu , Xu Zhou , Jun Ma , Zhenyu Wu , Zhaoji Jiang , Jiansheng Chen

GHz-peaked spectrum (GPS) radio sources are thought to be young objects which later evolve into FR-I and FR-II radio galaxies. We have used the Australia Telescope 20GHz (AT20G) survey catalogue to select a uniform sample of GPS sources…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Paul J. Hancock , Steven J. Tingay , Elaine M. Sadler , Chris Phillips , Adam T. Deller