Related papers: Emission line - radio correlation for Low Luminosi…

Data from a recent Australia Telescope Compact Array (ATCA) program of multi-frequency, multi-epoch monitoring of 202 active galactic nuclei with declinations < +10 degrees have been searched for GHz Peaked Spectrum (GPS) and Compact Steep…

We present morphological and photometric properties of 79 low redshift (z<0.12) radio galaxies extracted from two radio flux limited samples of radio sources. All objects are imaged in the R band and for a subsample we have also obtained B…

The evolutionary stage of a powerful radio source originated by an AGN is related to its linear size. In this context, compact symmetric objects (CSOs), which are powerful and intrinsically small (< 1 kpc) radio sources with a convex…

We present a rest-frame ultraviolet morphological analysis of 108 z=2.1 Lyman Alpha Emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S) and compare it to a similar sample of 171 LAEs at z=3.1. Using Hubble Space Telescope…

We present a radio/optical study of a sample of BL Lac objects at arcsecond and milliarcsecond resolution. The sample consists of 30 nearby (z<0.2) BL Lacs, mostly X-ray selected. These nearby objects are weak in the radio, yet we have…

Context: Narrow-band surveys for Ly-alpha emitters (LAEs) is a powerful tool in detecting high, and very high, redshift galaxies. Even though samples are growing at redshifts z = 3 - 6, the nature of these galaxies is still poorly known.…

A relativistic radio component, which moves in a direction close to the sky plane, will increase in flux density when it decelerates. This effect is the basis for the qualitative model for GPS galaxies we present in this paper, which can…

The interactions between radio-loud AGN and their environments play an important role in galaxy and cluster evolution. Recent work has demonstrated fundamental differences between High and Low Excitation Radio Galaxies (HERGs and LERGs),…

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…

I describe an observational program aimed at understanding the radio emission from distant, rapidly evolving galaxy populations. These observations were carried out at 1.4 and 8.5 GHz with the VLA centered on the Hubble Deep Field. Further…

Context. The advent of Fermi is changing our understanding on the radio and gamma-ray emission in Active Galactic Nuclei. Contrary to pre-Fermi ideas, BL Lac objects are found to be the most abundant emitters in the gamma-ray band. However,…

We present the results of HI and OH absorption measurements towards a sample of radio sources using the Arecibo 305-m telescope and the GMRT. In total, 27 radio sources were searched for associated 21-cm HI absorption. One totally new HI…

We present a large sample of 501 radio-selected BL Lac candidates from the combination of the Sloan Digital Sky Survey (SDSS) Data Release 5 optical spectroscopy and from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) radio…

The cross-correlation of the Sloan Digital Sky Survey Data Release 7 with the Faint Images of the Radio Sky at Twenty-Centimeters survey allows for a multiwavelength statistical study of radio-optical galaxy properties on a very large…

We study the environments of low- and high- excitation radio galaxies (LERGs and HERGs respectively) in the redshift range $0.01 < z < 0.4$, using a sample of 399 radio galaxies and environmental measurements from the Galaxy And Mass…

We compare the variability properties of very high energy gamma-ray emitting BL Lac objects in the optical and radio bands. We use the variability information to distinguish multiple emission components in the jet, to be used as a guidance…

We explore the viability of the unification of BL Lacs and FR I radio galaxies by comparing the core emission of radio galaxies with those of BL Lacs of similar extended radio power, taking advantage of the newly measured optical nuclear…

The CoNFIG (Combined NVSS-FIRST Galaxies) sample is a new sample of 274 bright radio sources at 1.4 GHz. It was defined by selecting all sources with S_1.4GHz > 1.3 Jy from the NRAO-VLA Sky Survey (NVSS) in the North field of the Faint…

Although radio observations have been historically seen as less valuable than optical observations, today's broadband radio spectra of peaked spectrum sources reveal detailed physics from within the inner region of the galaxy, on spatial…

Aims: We present optical spectroscopy of a sample of BL Lac objects, to determine their redshift, to study their broad emission line properties and to characterize their close environment. Methods: Twelve objects were observed using the ESO…