We present the results from a Chandra observation of the powerful radio galaxy 3C 265. We detect X–ray emission from the nucleus, the radio hotspots and lobes. In particular, the lobe X–ray emission is well explained as anisotropic inverse Compton scattering of the nuclear photons by the relativistic electrons in the radio lobes; the comparison between radio synchrotron and IC emission yields a...

The 120,000 X-ray sources detected in the RASS II processing of the ROSAT All-Sky Survey are correlated with the 14,315 IRAS galaxies selected from the IRAS Point Source Catalogue: 372 IRAS galaxies show X-ray emission within a distance of 100 arcsec from the infrared position. By inspecting the structure of the Xray emission in overlays on optical images we quantify the likelihood that the X-r...

We present evidence for a highly obscured X-ray source in one of two giant Lyα emission nebulae in the z = 3.09 proto-cluster region SSA22. Neither Lyα nebula is associated with significant radio emission. While one has a significant submillimeter detection and is undetected in the X-ray, the other is a factor of 2-10 times less submillimeter bright and appears to contain a hard-band X-ray sour...

A short Chandra ACIS-S observation of the Seyfert 2 galaxy IC 2560, which hosts a luminous nuclear water megamaser, shows: 1) the X-ray emission is extended; 2) the X-ray spectrum shows emission features in the soft (E < 2 keV) X-ray band; this is the major component of the extended emission; and 3) a very strong (EW∼ 3.6 keV) iron Kα line at 6.4 keV on a flat continuum. This last feature clear...

We present results from four recent Chandra monitoring observations of the jet in 3C 273 using the ACIS detector, obtained between November 2003 and July 2004. We find that the X-ray emission comes in two components: unresolved knots that are smaller than the corresponding optically emitting knots and a broad channel that is about the same width as the optical interknot region. We compute the j...

As accretion and merger shocks in clusters of galaxies may accelerate particles to high energies, clusters are candidate sites for the origin of ultra-high-energy (UHE) cosmic-rays. Recently, a prediction was presented for gamma-ray emission from a cluster of galaxies at a detectable level with modern imaging atmospheric Cherenkov telescopes. The gamma-ray emission was produced via inverse Comp...

Diffuse 511 keV line emission, from the annihilation of cold positrons, has been observed in the direction of the Galactic Centre for more than 30 years. The latest high-resolution maps of this emission produced by the SPI instrument on INTEGRAL suggest at least one component of the emission is spatially coincident with the distribution of ∼70 luminous, low-mass X-ray binaries detected in the s...

We discuss the extended X-ray emission seen in three archival Chandra observations, and one archival XMM-Newton observation, of the FRII radio galaxy Pictor A. The overall properties of the X-ray lobes are consistent with the conclusions of earlier workers that the extended X-ray emission is largely due to the inverse-Compton process, and the implied departure from equipartition is in the range...

The radiation of pulsars have been observed for many years. A few pulsars are discovered to have both radio and gamma-ray emission. Many models on pulsar radiation have been developed, but so far we are still lacking an elaborate model which can explain the emission from radio to gamma-rays in detail. In this paper we present a joint model for radio and gamma-ray emission, in which both the dom...