Related papers: Compactness of Weak Radio Sources at High Frequenc…

It is currently accepted that compact and bright radio sources characterized by a convex spectrum peaking at frequencies ranging from 100 MHz to a few GHz are young objects. In this scenario, high frequency peaker (HFP) radio sources, with…

We present Very Large Array (VLA) observations at 1.4 GHz and 5 GHz of a sample of 12 Quasi-stellar Objects (QSOs) at z = 3.99 to 4.46. The sources were selected as the brightest sources at 250 GHz from the recent survey of Omont et al.…

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…

Compact Symmetric Objects (CSOs) are small (less than 1 kpc) radio sources which have symmetric double lobes or jets. The dominant theory for the small size of these objects is that they are young radio sources which could grow into larger…

We have used the Very Large Array to search for compact milliarcsecond-size radio sources near methanol masers in high-mass star-forming regions. Such sources are required for Very Long Baseline Interferometry phase-referencing…

We present the results of EVN polarization observations of fourteen GHz-Peaked-Spectrum (GPS) radio sources at 5 GHz. These sources were selected from bright GPS source samples and we aimed at finding Compact Symmetric Objects (CSOs). We…

We present flux densities and polarization percentages of 159 radio galaxies based on nearly simultaneous VLA observations at four frequencies from 5 to 43GHz. This sample is selected from the high-frequency Australia Telescope 20GHz…

We use a new phase-calibration strategy to calibrate the phase of 86 GHz VLBI observations of the FR I radio galaxy NGC 4261. Instead of switching between a calibrator source and the target source, the target was observed while rapidly…

We have observed a small sample of powerful double radio sources (radio galaxies and quasars) at frequencies around 90 GHz with the BIMA millimetre array, with the intention of constraining the resolved high-frequency spectra of radio…

We defined a sub-sample of twelve GPS sources which have not been observed with the VLBI before, from the Parkes half-Jansky sample, and carried out VLBI observations at 1.6 GHz and 5 GHz with the European VLBI Network (EVN) in 2006 and…

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 <…

The Compact Symmetric Objects (CSOs) are small (<1 kiloparsec) and powerful extragalactic radio sources showing emission on both sides of an active galactic nucleus and no signs of strong relativistic beaming. They may be young radio…

We present pc-scale images of ten Compact Symmetric Objects (CSO) candidates observed with the European VLBI network (EVN). Five radio sources have been observed at 1.6 GHz, and five more at 2.3/8.4 GHz, the latter subsample with the…

The fields chosen for the first observations of the cosmic microwave background with the Very Small Array have been surveyed with the Ryle Telescope at 15 GHz. We have covered three regions around RA 00h20m Dec +30deg, RA 09h40m Dec +32deg…

We report early results of an observational campaign targeted on a sample of compact steep spectrum sources selected from the FIRST survey which are significantly weaker than those investigated before. The selection criteria and procedure…

We present preliminary results from the deepest VLBI observations yet conducted. VLBA+GBT 1.4 GHz observations of a region within NOAO-N, reach an r.m.s. noise level of 9 microJy per beam. Three sources are clearly detected (> 7 sigma)…

We present continent-scale VLBI - obtained with the European VLBI Network (EVN) at a wavelength of 18cm - of six distant, luminous submm-selected galaxies (SMGs). Our images have a synthesized beam width of ~30 milliarcsec FWHM - three…

We present results of multifrequency polarimetric VLBA observations of 34 compact radio sources. The observations are part of a large survey undertaken to identify CSOs Observed in the Northern Sky (COINS). Based on VLBI continuum surveys…

We present Very Long Baseline Interferometry observations of a faint and low-luminosity ($L_{\rm 1.4 GHz} < 10^{27}~\mbox{W Hz}^{-1}$) Gigahertz-Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) sample. We select eight sources from…

(Abridged) Conventional radio surveys of deep fields ordinarily have arc-second scale resolutions often insufficient to reliably separate radio emission in distant galaxies originating from star-formation and AGN-related activity. Very long…