相关论文: Jet Properties and Evolution in Small and Intermed…

The polarisation properties of the intrinsically small (< 20 kpc) radio sources are briefly discussed. At centimetric and decimetric wavelengths, substantial polarised emission is often detected in quasars and, at a lower level, in radio…

The Chandra discovery of bright X-ray emission from kpc-scale jets provides us unprecedented insights into the physical state of the plasma in the flow. In particular it is possible to get good constraints on the power and pressure in…

This paper reviews the evidence for interaction between radio jets and their environment in small and intermediate (sub-kpc) scale radio sources. Observations of gas (both neutral hydrogen and ionised gas) have shown the presence of fast (>…

The prospect of relativistic jets exhibiting complex morphologies as a consequence of geodetic precession has long been hypothesised. We have carried out a 3D hydrodynamics simulation study varying the precession cone angle, jet injection…

Large scale X-ray jets that extend to >100 kpc distances from the host galaxy indicate the importance of jets interactions with the environment on many different physical scales. Morphology of X-ray clusters indicate that the radio-jet…

QSOs' emission lines arise from highest velocity (approximately 10000 km/s), dense gas within approximately 0.1 parsec of the central engine, out to low-velocity, low-density gas at great distances from the host galaxy. In radio-loud QSOs…

Jets of compact radio sources are highly relativistic and Doppler boosted, making studies of their intrinsic properties difficult. Observed brightness temperatures can be used to study the intrinsic physical properties of the relativistic…

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…

A detailed analysis of the evolution of the properties of core-jet systems within the VLBA Imaging and Polarimetry Survey (VIPS) is presented. We find a power-law relationship between jet intensity and width that suggests for the typical…

We investigate the role discrete clumps embedded in an astrophysical jet play on the jet's morphology and line emission characteristics. By varying clumps' size, density, position, and velocity, we cover a range of parameter space motivated…

The parsec-scale total intensity structures of BL Lac objects share many characteristics with quasars: e.g. well-collimated jets and superluminal motion. However, the jets of BL Lac objects appear to fade much more quickly than those in…

Newly born and young radio sources are in a delicate phase of their life. Their jets are fighting their way through the surrounding gaseous medium, strongly experiencing this interaction while, at the same time, impacting and affecting the…

In previous papers we have discussed high-resolution observations of a large sample of powerful radio galaxies with z<0.3. Jets are detected in up to 80 per cent of the sample, and radio cores in nearly all the objects; in addition, we are…

It is currently accepted that intrinsically compact and bright radio sources characterized by a convex spectrum peaking at frequencies ranging from 100 MHz to a few GHz are young objects. Following the evolutionary models, these objects…

Compact radio emission provides a reliable method for the detection of low luminosity young stellar objects (YSOs), and is particularly useful for detecting the earliest stages of protostellar evolution where the source itself may still be…

We are developing a project aimed at studying the physical properties, origin and evolution of low-ionization structures in planetary nebulae. Within this project we have identified a number of pairs of highly collimated low-ionization…

There are numerous examples of radio sources with various sizes which surprisingly exhibit very similar morphology. This observational fact helped to create a standard evolutionary model in which young and small radio-loud active galactic…

We present an analysis of multi-epoch global VLBI observations of the Compact Symmetric Objects: 2352+495 and 0710+439 at 5 GHz. Analysis of data spread over almost two decades shows strong evidence for an increase in separation of the…

As the interface between the Sun's photosphere and corona, the chromosphere and transition region play a key role in the formation and acceleration of the solar wind. Observations from the Interface Region Imaging Spectrograph reveal the…

Compact steep-spectrum (CSS) and peaked spectrum (PS) radio sources are compact, powerful radio sources. The multi-frequency observational properties and current theories are reviewed with emphasis on developments since the earlier review…