相关论文: Parabolic jet shape on parsec scales in high redsh…

We are investigating the kinematics of jets in active galactic nuclei on parsec scales by studying a representative population of sources. This study is being carried out using the Very Long Baseline Array at 15 GHz, with more than 800…

We present simulations of relativistic jets propagating in a nonuniform medium. Specifically, we study the bending of jets propagating obliquely to the vector of the density-gradient. Our results are applied to the NGC 4258, where such a…

Preliminary VLBA polarisation results on 6 ``blazars'' from 6.5-cm to 7-mm are presented here. Observing at several different wavelengths, separated by short and long intervals, enabled reliable information about the magnetic (B) field…

We present numerical simulations of cold, axisymmetric, magnetically driven relativistic outflows. The outflows are initially sub-Alfv\'enic and Poynting flux-dominated, with total--to--rest-mass energy flux ratio up to $\mu \sim 620$. To…

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…

Relativistic jets of magnetized plasma are a common high-energy astrophysical phenomenon, observed across a wide range of spatial and energy scales. In the past, semianalytic meridionally self-similar models have proven highly successful in…

We study the kinematics of ridge lines on the pc-scale jet of the active galactic nucleus BL Lac. We show that the ridge lines display transverse patterns that move superluminally downstream, and that the moving patterns are analogous to…

We report new results from an HST archival program to study proper motions in the optical jet of the nearby radio galaxy M87. Using over 13 years of archival imaging, we reach accuracies below 0.1c in measuring the apparent velocities of…

A puzzling feature of the {\it Chandra}--detected quasar jets is that their X-ray emission decreases faster along the jet than their radio emission, resulting to an outward increasing radio to X-ray ratio. In some sources this behavior is…

Active galactic nuclei (AGN) show a range of morphologies and dynamical properties, which are determined not only by parameters intrinsic to the central engine but also their interaction with the surrounding environment. We investigate the…

Observations of both gamma-ray bursts (GRBs) and active galactic nuclei (AGNs) point to the idea that some relativistic jets are suffocated by their environment before we observe them. In these "choked" jets, all the jet's kinetic energy is…

X-ray emission from large scale extragalactic jets is likely to be due to inverse Compton scattering of relativistic particles off seed photons of both the cosmic microwave background field and the blazar nucleus. The first process…

Despite strong physical reasons that they should exist and decades of search, jets from the Galactic Center Black Hole, Sgr A*, have not yet been convincingly detected. Based on high-resolution Very Large Array images and ultra-deep…

The jet shape modification due to partonic energy loss in the dense QCD matter is investigated by the help of the special transverse energy-energy correlator in the vicinity of maximum energy deposition of every event. In the accepted…

The magnetic field plays a significant role in the phenomenon of highly collimated jets of active galactic nuclei (AGN). Relativistic effects prevent the direct reconstruction of the magnetic field direction as transverse to electric…

Flares in radio-loud AGN are thought to be associated with the injection of fresh plasma into the compact jet base. Such flares are usually strongest and appear earlier at shorter radio wavelengths. Hence, VLBI at mm-wavelengths is best…

The Very Large Array has been used at five frequencies to study the structure and linear polarization of SS433 on scales as small as ~0.1" ~ 500 AU. Each jet consists of a sharp, curving ridge-line at the leading edge, plus significant…

The apparent position of the "core" in a parsec-scale radio jet (a compact, bright emitting region at the narrow end of the jet) depends on the observing frequency, owing to synchrotron self-absorption and external absorption. While…

Gamma-Ray Bursts (GRBs) are now considered as relativistic jets. We analyze the gravitational waves from the acceleration stage of the GRB jets. We show that (i) the point mass approximation is not appropriate if the opening half-angle of…

We have investigated particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma. Strong magnetic fields generated in the trailing jet shock lead to transverse…