相关论文: High-redshift radio galaxies: at the crossroads
Active Galactic Nuclei (AGN) are traditionally divided empirically into two main classes: "radio-loud" and "radio-quiet" sources. These labels, which are more than fifty years old, are obsolete, misleading, and wrong. I argue that AGN…
At the turn of the decade we arguably move from the era of precision cosmology to the era of galaxy formation. One approach to this problem will be via the construction of comprehensive galaxy samples. In this review I take the opportunity…
The intense star formation in starburst galaxies results in the formation of intense winds that sweep matter up to several kpc out of the galactic plane. These winds can be detected in many bands of the electromagnetic spectrum. In this…
Investigation of the triggering mechanisms of radio AGN is important for improving our general understanding of galaxy evolution. In the first paper in this series, detailed morphological analysis of high-excitation radio galaxies (HERGs)…
We address the nature of broad-lined radio galaxies, in particular their radio axis orientation, using new, matched resolution, dual frequency radio observations of a sample of twelve nearby broad-lined extragalactic 3C objects. Radio…
Energetic feedback from active galactic nuclei (AGN) is an important ingredient for regulating the star-formation history of galaxies in models of galaxy formation, which makes it important to study how AGN feedback actually occurs in…
Radio galaxies can be seen out to very high redshifts, where in principle they can serve as probes of the early evolution of the Universe. Here we show that for any model of radio-galaxy evolution in which the luminosity decreases with time…
Radio activity in AGN (Active Galactic Nuclei) produce feedback on the host galaxy via the impact of the relativistic jets on the circumnuclear gas. Although radio jets can reach up to several times the optical radius of the host galaxy, in…
That jetted active galactic nuclei (AGN) are also hosted in spiral galaxies is now well established. Our understanding of how such objects might fit in the radio loud AGN subclass has been described by Foschini and others over the past…
Winged, or X-shaped, radio sources form a small class of morphologically peculiar extragalactic sources. We present multi-frequency radio observations of two such sources. We derive maximum ages since any re-injection of fresh particles of…
Cosmic rays (CRs) are thought to be an important feedback mechanism in star-forming galaxies. They can provide an important source of pressure support and possibly drive outflows. We perform multidimensional CR-magnetohydrodynamic…
I summarize Xray properties of high redshift radio galaxies, beginning with a brief review of what has been learned from Xray observations of low redshift powerful radio galaxies (in particular, Cygnus A), and then turning to Chandra…
AGN feedback is a well known mechanism in the evolution of galaxies. One open question is the driving mechanism of galaxy-scale outflows. At low redshift, radio jets often interact with the ISM, generating turbulence and driving ionized…
At redshift larger than 3 there is a disagreement between the number of blazars (whose jet is pointing at us) and the number of expected parents (whose jet is pointing elsewhere). Now we strengthen this claim because (i) the number of…
We review the statistical properties of the main populations of radio sources, as emerging from radio and millimeter sky surveys. Recent determinations of local luminosity functions are presented and compared with earlier estimates still in…
Outflows and jets launched from the nuclei of galaxies emit radio synchrotron emission that can be used to study the impact of accretion energy on the host galaxy. The decades-long baseline now enabled by large radio surveys allows us to…
The role of starburst winds versus active galactic nuclei (AGN) jets/winds in the formation of the kiloparsec scale radio emission seen in Seyferts is not yet well understood. In order to be able to disentangle the role of various…
We present a combined radio/X-ray study of six massive galaxy clusters, aimed at determining the potential for heating of the intra-cluster medium (ICM) by non-central radio galaxies. Since X-ray cavities associated with the radio lobes of…
Active galactic nuclei (AGNs) are known to cover an extremely broad range of radio luminosities and the spread of their radio-loudness is very large at any value of the Eddington ratio. This implies very diverse jet production efficiencies…
Radio astronomy has changed. For years it studied relatively rare sources, which emit mostly non-thermal radiation across the entire electromagnetic spectrum, i.e. radio quasars and radio galaxies. Now it is reaching such faint flux…