Related papers: Where Centaurus A gets its X-ray knottiness
Seyfert galaxies and quasars were first discovered through optical and radio techniques, but in recent years high-energy emission, that can penetrate central gas and dust, has become essentially the defining characteristic of an AGN. AGNs…
A widely discussed explanation for the origin of the X-ray emission observed from knots in extended quasar jets with the Chandra X-ray Obseratory is Compton-scattered CMBR by electrons with Lorentz factors $\gamma^\prime \sim 10^2$. This…
I present here a short personal view of our understanding of the Chandra detected knots and hot spots of powerful Fanaroff Rilley (FR) II radio galaxies and quasars in the context of leptonic models. Observations of the knots and hot spots…
We consider the evolution of a spherically expanding plasma cloud, where there is continuous injection of non-thermal electrons. We compute the time dependent electron distribution and resultant photon spectra taking into account…
We report results from Chandra observations of the X-ray jet of 3C~273 during the calibration phase in 2000 January. The zeroeth-order images and spectra from two 40-ks exposures with the HETG and LETG+ACIS-S show a complex X-ray structure.…
A Chandra X-ray imaging observation of the jet in Pictor A showed a feature that appears to be a flare that faded between 2000 and 2002. The feature was not detected in a follow-up observation in 2009. The jet itself is over 150 kpc long…
The X-ray spectra of black hole binaries in the low/hard state first harden as the flux decreases, then soften. This change in behaviour has been variously attributed to either the X-rays switching from being produced in the flow to being…
Context: HH 158, the jet from the young star DG Tau, is one of the few sources of its type where jet knots have been detected at optical and X-ray wavelengths. Aims: To search, using Very Large Array observations of this source, radio knots…
The radio galaxy M87 is well known for its jet, which features a series of bright knots observable from radio to X-ray wavelengths. We analyze the X-ray image and flux variability of the knot HST-1 in the jet. Our analysis includes all 112…
X-ray observations of kilo-parsec scale jets indicate that a synchrotron origin of the sustained non-thermal emission is likely. This requires distributed acceleration of electrons up to near PeV energies along the jet. The underlying…
Neumayer et al. established the existence of a blue-shifted cloud in the core of Centaurus A, within a few parsecs of the nucleus and close to the radio jet. We propose that the cloud has been impacted by the jet, and that it is in the…
We report continuum GMRT observations aimed to explore the behavior of the jet associated with IRAS 16547-4247 at very low frequencies (325 MHz and 610 MHz). The obtained maps reveal an elongated morphology in the SE-NW direction. In…
For the interpretation of X-ray radiation from kiloparsec jets of quasars, the inverse Compton scattering of the cosmic microwave background has been widely used for almost 20 years. A recent analysis of the Fermi-LAT observational data…
We present a long-slit spectrum of the Herbig-Haro object HH 111, obtained with SITS on the Hubble Space Telescope. This spectrum has a spectral resolution of approx. 50 km/s, so it gives a good picture of the kinematical properties of the…
We present a detailed study of the X-ray, optical and radio emission from the jet, lobes and core of the quasar PKS 2101-490 as revealed by new Chandra, HST and ATCA images. We extract the radio to X-ray spectral energy distributions from…
We present an analysis of a Chandra observation of the field surrounding the low-mass X-ray binary 4U 1755-33, which has been in quiescence since 1996. In 2003, Angelini and White reported the appearance of a narrow 7 arcmin long jetlike…
High angular resolution VLBI observations of Centaurus A have been undertaken that allow access to a wide field-of-view, encompassing both the well-studied pc-scale jet and the inner part of the kpc-scale jet. The VLBI observations have…
Motivated by the large number of jets detected by the Chandra X-ray Observatory, and by the inverse Compton X-ray emission model (IC/CMB) for relativistic jets, we revisit two basic questions: ``If the medium that carries the jet's energy…
The UV continuum spectrum of quasars and AGN is assumed to originate from an accreting disk surrounding a massive rotating black hole. We discuss the structure and emission spectra of a disk which drives a powerful jet. Due to the large…
Relativistic jets are among the most fascinating objects in the Universe, and recent high-resolution Very Long Baseline Interferometric (VLBI) observations, including the Global mm-VLBI Array and the Event Horizon Telescope (EHT), are able…