Related papers: The VLBA Calibrator Survey - VCS1
We report on first results of an ongoing effort to image a small sample of high-redshift radio galaxies (HzRGs) with milliarcsecond (mas) resolution, using very-long-baseline interferometry (VLBI) techniques. Here, we present 1.7 and 5.0…
High-redshift radio-loud quasars are used to, among other things, test the predictions of cosmological models, set constraints on black hole growth in the early universe and understand galaxy evolution. Prior to this paper, 20 extragalactic…
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…
We present a series of sixteen Very Long Baseline Array (VLBA) high angular resolution observations of a cluster of suspected low-mass young stars in the Monoceros R2 region. Four compact and highly variable radio sources are detected;…
We introduce a new survey to map the radio continuum halos of a sample of 35 edge-on spiral galaxies at 1.5 GHz and 6 GHz in all polarization products. The survey is exploiting the new wide bandwidth capabilities of the Karl G. Jansky Very…
We have previously presented the results of a 325 MHz radio survey of M31, conducted with the A-configuration of the Very Large Array. In this survey, a total of 405 radio sources between <6" and 170" in extent were mapped with a resolution…
We present a status report on our search for multiple-image QSOs among southern radio sources. Our goal is to identify new lenses for use in studies of cosmology and galaxy structure. To date we have examined 3300 radio sources, identified…
We are pursuing a project to build a database of phase calibration sources suitable for Giant Metrewave Radio Telescope (GMRT). Here we present the first release of 45 low frequency calibration sources at 235 MHz and 610 MHz. These…
Aims. We use near-infrared, ground-based data from the VISTA Variables in the Via Lactea (VVV) survey to indirectly extend the astrometry provided by the Gaia catalog to objects in heavily-extincted regions towards the Galactic bulge and…
We have obtained mas-scale resolution very long baseline interferometry (VLBI) images of a sample of Seyfert 1 and Seyfert 2 galaxies at 5 GHz (wavelength, $\lambda$ = 6 cm). The Seyferts of the two types were chosen to be matched in…
We have used the Very Large Array (VLA) to conduct a survey for radio continuum emission in the sample of 52 Seyfert nuclei selected from the optical spectroscopic galaxy catalog of Ho, Filippenko, and Sargent. This Seyfert sample is the…
(Abridged) Context: The Red MSX Source (RMS) survey is an ongoing multi-wavelength observational programme designed to return a large, well-selected sample of massive young stellar objects (MYSOs). We have identified $\sim$2000 MYSO…
We discuss the importance of the direct link between the most accurate radio and optical reference frames that will become possible with the next-generation space astrometry missions in about a decade. The positions of more than 500 active…
As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…
The Very Large Array (VLA) Low-frequency Sky Survey (VLSS) has imaged 95% of the 3*pi sr of sky north of declination = -30 degrees at a frequency of 74 MHz (4 meter wavelength). The resolution is 80" (FWHM) throughout, and the typical RMS…
We present a catalogue of a large sample of extended radio sources in the SCORPIO field, observed and resolved by the Australia Telescope Compact Array. SCORPIO, a pathfinder project for addressing the early operations of the Australia SKA…
From 43GHz VLBA observations of the pair of radio sources 1928+738 and 2007+777 we have demonstrated the feasibility of precision phase-delay differential astrometric techniques at millimeter wavelengths. For a pair of sources with 5…
A new version of the Optical Characteristics of Astrometric Radio Sources (OCARS) catalog is presented. This compiled catalog includes radio sources observed in different VLBI programs and experiments that result in source position…
The extraordinary astrometric accuracy of radio interferometry creates an important and unique opportunity for the discovery and characterization of exo-planets. Currently, the Very Long Baseline Array can routinely achieve better than 100…
We report on a recent 90 cm wide-field VLBI survey of two 3.1 deg^2 fields using the VLBA, Westerbork and Jodrell Bank telescopes. In-beam calibration was used to calibrate each field, the process was simplified by imaging the calibrators…