English
Related papers

Related papers: Compact source resolution and rapid variability in…

200 papers

We present observations at 1.7 and 8.4 GHz of two Compact Steep Spectrum (CSS) sources from a complete sample of low-intermediate power radio galaxies. 3C346 shows an asymmetric structure with a one-sided ``jet'' and ``hot spot''. Present…

Astrophysics · Physics 2009-10-28 W. D. Cotton , L. Feretti , G. Giovannini , T. Venturi , L. Lara , J. Marcaide , A. E. Wehrle

The Local Group dwarf elliptical galaxy M32 hosts one of the nearest and most under-luminous super-massive black holes (SMBHs) ever known, offering a rare opportunity to study the physics of accreting SMBHs at the most quiescent state.…

Astrophysics of Galaxies · Physics 2020-05-13 Sijia Peng , Zhiyuan Li , Loránt O. Sjouwerman , Yang Yang , Fuguo Xie , Feng Yuan

Observations of the starburst galaxy, M82, have been made with the VLA in its A-configuration at 15 GHz and MERLIN at 5 GHz enabling a spectral analysis of the compact radio structure on a scale of < 0.1'' (1.6 pc). Crucial to these…

Astrophysics · Physics 2009-11-07 A. R. McDonald , T. W. B. Muxlow , K. A. Wills , A. Pedlar , R. J. Beswick

We have made sensitive milliarcsecond-resolution radio images of the nearby merger galaxy Arp 299 at four epochs spread over 18 months between 2003 and 2005. The combined data revealed a total of 30 point sources in the two primary merger…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 James S. Ulvestad

SN 2001em, identified as a Type Ic supernova, has recently been detected in the radio and X-rays, $\gtrsim$ 2 yr after the explosion. The high luminosities at such late times might arise from a relativistic jet viewed substantially off-axis…

Astrophysics · Physics 2009-11-10 Jonathan Granot , Enrico Ramirez-Ruiz

NGC 6240 is a luminous infrared galaxy that, based on recent MERLIN and CHANDRA observations, appears to host a pair of active galactic nuclei. We present new, multiepoch and multifrequency radio observations of NGC 6240 obtained using the…

Astrophysics · Physics 2009-11-10 Jack F. Gallimore , Robert Beswick

We have used the VLBA at 5 GHz to observe all galaxies with nuclear radio flux densities above 3.5 mJy found in a VLA survey at 15 GHz of a sample of nearby LINER galaxies. All galaxies were detected revealing high brightness temperature…

Astrophysics · Physics 2009-10-31 Heino Falcke , Neil M. Nagar , Andrew S. Wilson , James S. Ulvestad

We report the appearance of a new radio source at a projected offset of 460 pc from the nucleus of Cygnus A. The flux density of the source (which we designate Cygnus A-2) rose from an upper limit of <0.5 mJy in 1989 to 4 mJy in 2016…

High Energy Astrophysical Phenomena · Physics 2017-06-02 Daniel A. Perley , Richard A. Perley , Vivek Dhawan , Christopher L. Carilli

We present high-resolution radio observations of a sample of 65 radio sources at low Galactic latitudes. The sources were all observed at 5 GHz with the Very Large Array A-array. MERLIN observations at 5 GHz of the ultracompact HII region…

Astrophysics · Physics 2009-11-10 D. J. Saikia , P. Thomasson , S. Roy , A. Pedlar , T. W. B. Muxlow

Using three epochs of VLA observations of the Galactic Plane in the first quadrant taken ~15 years apart, we have conducted a search for a population of variable Galactic radio emitters in the flux density range 1-100 mJy at 6 cm. We find…

Astrophysics of Galaxies · Physics 2015-05-18 Robert H. Becker , David J. Helfand , Richard L. White , Deanne D. Proctor

The identification of persistent radio sources (PRSs) coincident with two repeating fast radio bursts (FRBs) supports FRB theories requiring a compact central engine. However, deep non-detections in other cases highlight the diversity of…

We present new Karl G. Jansky Very Large Array radio continuum images of the nuclei of Arp 220, the nearest ultra-luminous infrared galaxy. These images have both the angular resolution to study detailed morphologies of the two nuclei that…

We are entering a new era of sensitive, large-area and multi-frequency radio surveys that will allow us to identify Gigahertz-Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources over a wide range in radio luminosity and…

Astrophysics of Galaxies · Physics 2016-03-16 Elaine M. Sadler

We report Subaru/PFS spectroscopic follow-up of a radio-loud quasar at $z=1.715$ from the UNVEIL radio AGN catalog and with X-ray detections. The PFS spectrum displays a broad MgII emission line with an $\mathrm{FWHM}\gtrsim4000\ km/s$,…

We present new radio continuum images and a source catalogue from the MeerKAT survey in the direction of the Small Magellanic Cloud (SMC). The observations, at a central frequency of 1.3 GHz across a bandwidth of 0.8 GHz, encompass a field…

We present a radio survey of X-ray sources in the Large and Small Magellanic clouds with the Australia Telescope Compact Array at 6.3 and 3.5 cm. Specifically, we have observed the fields of five LMC and two SMC supersoft X-ray sources, the…

Astrophysics · Physics 2009-10-30 R. P. Fender , K. Southwell , A. K. Tzioumis

Here we discuss evolution and broad-band emission of compact (< kpc) lobes in young radio sources. We propose a simple dynamical description for these objects, consisting of a relativistic jet propagating into a uniform gaseous medium in…

Astrophysics · Physics 2009-11-13 L. Stawarz , L. Ostorero , M. C. Begelman , R. Moderski , J. Kataoka , S. Wagner

We present partial results from our monitoring of the nuclear region of the starburst galaxy IC 694 (=Arp 299-A) at radio wavelengths, aimed at discovering recently exploded CCSNe, as well as to determine their rate of explosion, which…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-22 Miguel A. Perez-Torres , Antonio Alberdi , Cristina Romero-Canizales , Marco Bondi , Antonis Polatidis

Jets of high-redshift active galactic nuclei (AGNs) can be used to directly probe the activity of the black holes in the early Universe. Radio sources with jets misaligned with respect to the line of sight are expected to dominate the…

High Energy Astrophysical Phenomena · Physics 2021-08-18 Yingkang Zhang , Tao An , Sándor Frey , Xiaolong Yang , Máté Krezinger , Oleg Titov , Alexey Melnikov , Pablo de Vicente , Fengchun Shu , Ailing Wang

We have identified 127 discrete sources in a Chandra observation of M83, with a detection limit of ~ 3 x 10^{36} erg/s in the 0.3-8.0 keV band. We discuss the individual properties of about 20 bright sources with L_x >~ 10^{38} erg/s, and…

Astrophysics · Physics 2009-11-10 Roberto Soria , Kinwah Wu