相关论文: Parsec Scale Properties of Radio Sources

A complete sample of 27 radio galaxies was selected from the B2 and 3CR catalogs, in order to study their properties on the milliarcsecond scale. In the Appendix of this paper we present new radio images for 12 of them. Thanks to the…

The different methods to derive the jet velocity and orientation on the parsec scale are presented. From these methods I will discuss the velocity distribution of parsec scale jets and the possible presence of acceleration or deceleration…

Kinematic and spectral studies are improving our knowledge of the age distribution in compact radio sources, providing evidence that small sources are generally very young. The properties of jets in objects spanning the size range from a…

We present a new, complete, sample of 95 radio sources selected from the B2 and 3CR catalogues, with z < 0.1. Since no selection effect on the core radio power, jet velocity, or source orientation is present, this sample is well suited for…

We present an update of the parsec scale properties of the Bologna Complete Sample consisting of 95 radio sources with z $<$ 0.1 from the B2 Catalog of Radio Sources and the Third Cambridge Revised Catalog (3CR). Thanks to new data obtained…

We report the most important results on the parsec-scale properties of a complete sample of radio galaxies carried out at radio frequencies with the Global VLBI array and with the VLBA. Relativistic parsec-scale jets are common both in FRI…

We investigate the sample of 213 GPS sources selected from simultaneous multi-frequency 1-22 GHz observations obtained with RATAN-600 radio telescope. We use publicly available data to characterize parsec-scale structure of the selected…

The evolution of symmetric extragalactic radio sources can be characterized by four distinct growth stages of the radio luminosity versus size of the source. The interaction of the jet with the ambient medium results in the formation and…

We are conducting a multi-wavelength (radio, optical, and X-ray) observational campaign to classify, morphologically and physically, a sample of 55 flat-spectrum radio sources dominated by structure on kpc-scales. This sample contains 22…

The parsec scale properties of low power radio galaxies are reviewed here, using the available data on 12 FR I galaxies. The most frequent radio structure is an asymmetric parsec-scale morphology, i.e. core and one-sided jet. It is shared…

To study statistical properties of different classes of sources, it is necessary to observe a sample that is free of selection effects. To do this, we initiated a project to observe a complete sample of radio galaxies selected from the B2…

We present a new sample of 30 nearby (z<0.2) BL Lacs, selected to study the nuclear as well as the large scale properties of low power radio sources. In this first paper, we show and discuss new radio data taken with the VLA (19 objects at…

We present new radio data completing the imaging for a sample of 30 nearby (z < 0.2) BL Lac objects on parsec and kiloparsec scale. The sample is composed of both high and low luminosity sources and it is therefore an ideal test bed for…

We present here new VLBI observations of one FR-I radio galaxy (NGC2484) and two Broad Line FR-II radio galaxies (3C109 and 3C382). For 3C109 new VLA maps are also shown. These sources belong to a complete sample of radio galaxies under…

Parsec scale jet properties are shortly presented and discussed. Observational data are used to derive constraints on the jet velocity and orientation, the presence of velocity structures, and the connection between the pc and kpc scale.…

The statistical study of the parsec scale properties of radio sources is crucial to get information on the nature of the central engine and to provide the foundations of the current unified theories, suggesting that the appearance of active…

Compact steep spectrum (CSS) and GHz-peaked spectrum (GPS) radio sources represent a large fraction of the extragalactic objects in flux density-limited samples. They are compact, powerful radio sources whose synchrotron peak frequency…

We present high resolution images of the radio source 3C 84 at 43 GHz, from 121 observations conducted by the BEAM-ME monitoring program between 2010 and 2023. Imaging was performed using the recent forward modeling imaging method…

Broad absorption line quasars (BAL QSOs) belong to a class of objects not well-understood as yet. Their UV spectra show BALs in the blue wings of the UV resonance lines, owing to ionized gas with outflow velocities up to 0.2 c. They can…

We report the high-resolution radio observations of eight Fanaroff-Riley type 0 radio galaxies (FR 0s), selected from the published FR 0 sample. These observations were carried out with the Very Long Baseline Array (VLBA) and European VLBI…