相关论文: Jets in Quasars
The observational evidence for jets and phenomena arising from rotation powered radio pulsars is reviewed, including many recent and exciting discoveries at X-ray wavelengths. The well studied jets of the Crab pulsar are summarised,…
We use statistical results from a large sample of about 500 blazars, based on two surveys, the Deep X-ray Radio Blazar Survey (DXRBS), nearly complete, and the RASS-Green Bank survey (RGB), to provide new constraints on the spectral energy…
Relativistic stellar jets, produced in binary systems called microquasars, propagate through media with different spatial scales releasing their energy in the form of work and radiation from radio to gamma rays. There are several…
The radiative and jet power in active galactic nuclei is generated by accretion of material on to supermassive galactic-centre black holes. For quasars, where the radiative power is by definition very high, objects with high radio…
Jets can be probed in their innermost regions (d~0.1 pc) through the study of the relativistically-boosted emission of blazars. On the other extreme of spatial scales, the study of structure and dynamics of extragalactic relativistic jets…
Collimated outflows (jets) appear to be a ubiquitous phenomenon associated with the accretion of material onto a compact object. Despite this ubiquity, many fundamental physics aspects of jets are still poorly understood and constrained.…
Two rival hypotheses have been proposed for the origin of the compact radio flux observed in radio-quiet quasars (RQQs). It has been suggested that the radio emission in these objects, typically some two or three orders of magnitude less…
I present an overview of past, present and future research on microquasars and jets, showing that microquasars, i.e. galactic jet sources, are among the best laboratories for high energy phenomena and astroparticle physics. After reminding…
The central black-hole masses of a sample of radio-loud quasars are estimated by using the data of $H_{\beta}$ line-width and the optical continuum luminosity. The vast majority of the quasars in this sample have black-hole masses larger…
Microquasars are sources of very high-energy gamma-rays and, very probably, high-energy gamma-ray emitters. We propose a model for a jet that can allow to give accurate observational predictions for jet emission at different energies and…
We present Chandra X-ray observations of 14 radio-loud quasars at redshifts $3 < z < 4$, selected from a well-defined sample. All quasars are detected in the 0.5-7.0 keV energy band, and resolved X-ray features are detected in five of the…
Long-lasting, very bright multiwavelength flares of blazar jets are a curious phenomenon. The interaction of a large gas cloud with the jet of a blazar may serve as a reservoir of particles entrained by the jet. The size and density…
Blazar spectra are one of the most important windows into the physical processes occurring along jets. The spectrum, composed from the different emitting regions along the jet, allows us to constrain the physical conditions in the jet. I…
We examine the distribution of radio emission from ~42,000 quasars from the Sloan Digital Sky Survey, as measured in the LOFAR Two-Metre Sky Survey (LoTSS). We present a model of the radio luminosity distribution of the quasars that assumes…
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…
Microquasars provide new insights into: 1) the physics of relativistic jets from black holes, 2) the connection between accretion and ejection, and 3) the physical mechanisms in the formation of stellar-mass black holes. Furthermore, the…
We estimate the power of relativistic, extragalactic jets by modelling the spectral energy distribution of a large number of blazars. We adopt a simple one-zone, homogeneous, leptonic synchrotron and inverse Compton model, taking into…
We use frequency-dependent position shifts of flat spectrum radio cores to estimate the kinetic power of AGN jets. We find a correlation between the derived jet powers and AGN narrow-line luminosity, consistent with the well-known relation…
I review some of the basic observational details of jets from X-ray binaries, or `microquasars'. It is shown that in both (Z and Atoll) NS and BHC systems radio emission, and therefore jet formation, is correlated with the presence of hard…
Jets are expected to play a prominent role in the ongoing efforts to characterize the hot and dense QCD medium created in ultrarelativistic heavy ion collisions. The success of this program depends crucially on the existence of a full…