相关论文: The X-Ray Cavity Around Hotspot E in Cygnus A: Tun…

Our Chandra observation of the FRI radio galaxy 3C66B has resulted in the first detection of an X-ray counterpart to the previously known radio, infra-red and optical jet. The X-ray jet is detected up to 7 arcsec from the core and has a…

We have made ROSAT PSPC and HRI X-ray observations to study the intracluster gas surrounding the powerful radio source Hercules A. The cluster is luminous in X-rays (L_bol = 4.8x10^37 W), and the host of the radio source is the central…

We present a collection of double-lobed sources towards a 20 sq deg area of the Cygnus region at the northern sky, observed at 325 and 610~MHz with the Giant Metrewave Radio Telescope. The 10'' resolution achieved at 325 MHz is 5.5 times…

ROSAT High Resolution Imager (HRI) data from eight observations have been co-added to obtain an effective exposure of 230 ksec. We have identified a number of features and regions with excess X-ray brightness over that from a circularly…

We examine Chandra observations of the powerful Fanaroff-Riley class II (FR II) radio galaxy Cygnus A for an X-ray counterpart to the radio transient Cygnus A-2 that was first detected in 2011. Observations are performed using the…

We present new {\it Chandra} observations of the radio galaxy 3C 445, centered on its southern radio hotspot. Our observations detect X-ray emission displaced upstream and to the west of the radio-optical hotspot. Attempting to reproduce…

We report the discovery of a transient radio source 2.7 arcsec (0.1 pc projected distance) South of the Galactic Center massive black hole, Sagittarius A*. The source flared with a peak of at least 80 mJy in March 2004. The source was…

We present results of our detailed theoretical study of the observed orbital modulation of the radio emission in Cyg X-1. The modulation occurs due to free-free absorption in the wind from the companion star varying with the orbital phase,…

The radio lobes of Hydra A lie within cavities surrounded by a rim of enhanced X-ray emission in the intracluster gas. Although the bright rim appears cooler than the surrounding gas, existing Chandra data do not exclude the possibility…

There is good evidence for X-ray emission associated with AGN jets which are relativistically boosted towards the observer. But to what jet radius does such X-ray emission persist? To attempt to answer this question one can look at radio…

We report on new 1.41 GHz Green Bank Telescope and 352 MHz Westerbork Synthesis Radio Telescope observations of the Coma cluster and its environs. At 1.41 GHz we tentatively detect an extension to the Coma cluster radio relic source…

We report new HST WFPC2 and NICMOS observations of the center of the nearest radio galaxy Centaurus A (NGC 5128) and discuss their implications for our understanding of the active nucleus and jet. We detect the active nucleus in the near-IR…

The prototypical powerful FR \Romannum{2} radio galaxy Cygnus A fits extremely well into the quasar/radio galaxy unified model: high polarization with an angle almost perpendicular to the radio jet and polarized flux showing broad permitted…

We have studied the structure and energetics of the powerful microquasar/shock-ionized nebula S26 in NGC 7793, with particular focus on its radio and X-ray properties. Using the Australia Telescope Compact Array, we have resolved for the…

We report on VLBI observations of M81*, the northwest-southeast oriented nuclear core-jet source of the spiral galaxy M81, at five different frequencies between 1.7 and 14.8 GHz. By phase referencing to supernova 1993J we can accurately…

Because of their inherently high flux allowing the detection of clear signals, black hole X-ray binaries are interesting candidates for polarization studies, even if no polarization signals have been observed from them before. Such…

High energy gamma-rays have been detected from Cygnus X-3, a system composed of a Wolf-Rayet star and a black hole or neutron star. The gamma-ray emission is linked to the radio emission from the jet launched in the system. The flux is…

Very-long-baseline interferometry (VLBI) observations of active galactic nuclei at millimeter wavelengths have the power to reveal the launching and initial collimation region of extragalactic radio jets, down to $10-100$ gravitational…

We present U, V, and I-band images of the host galaxy of Hercules A (3C 348) obtained with HST/WFC3/UVIS. We find a network of dusty filaments which are more complex and extended than seen in earlier HST observations. The filaments are…

We report the first detection, with Chandra, of X-ray emission from the jet of the powerful narrow-line radio galaxy 3C 346. X-rays are detected from the bright radio and optical knot at which the jet apparently bends by about 70 degrees.…