Related papers: Diffuse X-ray emission in the Cygnus OB2 associati…
The soft X-ray background shows a general enhancement toward the inner region of the Galaxy. But whether this enhancement is a local feature (e.g., a superbubble within a distance of <= 200 pc) and/or a phenomenon related to energetic…
We present results from 300 ks of X-ray observations of the Chandra Deep Field South. The field of the four combined exposures is now 0.1035 deg^2 and we reach a flux limit of 10^{-16} erg s^{-1} cm^{-2} in the 0.5-2 keV soft band and…
The X-ray emission from most accreting white dwarfs (WDs) in symbiotic binary stars is quite soft. Several symbiotic WDs, however, produce strong X-ray emission at energies greater than ~20 keV. The Swift BAT instrument has detected hard…
We present the results of a detailed correlation study between the soft X-ray, hard X-ray, and radio emission (obtained from RXTE ASM, BATSE, and GBI observations, respectively) of the bright radio emitting Galactic X-ray binary Cygnus X-3.…
High-resolution Halpha monitoring of Cyg X-1, HD226868 was carried out during 1996-2002 and the resultant spectra analysed in conjunction with 1.5-12 keV X-ray monitoring. We demonstrate that the Halpha line-profiles have complex…
Massive, early type stars have been detected as radio sources for many decades. Their thermal winds radiate free-free continuum and in binary systems hosting a colliding-wind region, non-thermal emission has also been detected. To date, the…
RT Cru belongs to the rare class of hard X-ray emitting symbiotics, whose origin is not yet fully understood. In this work, we have conducted a detailed spectroscopic analysis of X-ray emission from RT Cru based on observations taken by the…
High energy emissions near particle accelerators provide unique windows to probe the particle acceleration and ensuing escape process determined by local medium properties, particularly the turbulence properties. It has been demonstrated…
It is commonly adopted that X-rays from O stars are produced deep inside the stellar wind, and transported outwards through the bulk of the expanding matter which attenuates the radiation and affects the shape of emission line profiles.…
We provide constraints on the nature of the optically faint (I>=24) X-ray source population from a 1 Ms Chandra exposure of a 8.4x8.4 arcmin region containing the Hubble Deep Field North. We detect 47 (2,400 deg^-2) optically faint X-ray…
We report the first localization of diffuse, non-thermal, X-ray emission from a nearby galaxy cluster. Using Chandra data, we have isolated a diffuse non-thermal X-ray component with a photon index, Gamma_ X = 2.21 +0.14 -0.15 and a flux of…
We present Cygnus X in a new multi-wavelength perspective based on an unbiased BLAST survey at 250, 350, and 500 micron, combined with rich datasets for this well-studied region. Our primary goal is to investigate the early stages of high…
We present the results of a Suzaku spectroscopic study of the soft extended X-ray emission in the HII region M17. The spectrum of the extended emission was obtained with a high signal-to-noise ratio in a spatially-resolved manner using the…
We present high resolution X-ray observations of the narrow line radio galaxy PKS 1138-262 at z = 2.156 with the ACIS-S detector on the Chandra observatory. These observations show that the X-ray emission from 1138-262 is dominated by…
We present the first Chandra/ACIS imaging study of the circumnuclear region of the nearby Seyfert galaxy NGC 1365. The X-ray emission is resolved into point-like sources and complex, extended emission. The X-ray morphology of the extended…
We present results from the zeroth-order imaging of a Chandra HETGS observation of the nearby Seyfert 2 galaxy Circinus. Twelve X-ray sources were detected in the ACIS-S image of the galaxy, embedded in diffuse X-ray emission. The latter…
High-resolution X-ray spectra of O-type stars revealed less wind absorption than expected from smooth winds with conventional mass-loss rates. Various solutions have been proposed, including porous winds, optically thick clumps or an…
Deep Chandra exposures reveal the presence of diffuse X-ray emission with a luminosity of 1.3x10^{39} ergs s^{-1} from the spiral galaxy NGC 3184. This appears to be truly diffuse thermal emission distinct from the low-luminosity LMXB…
We present time-resolved and phase-resolved variability studies of an extensive X-ray high-resolution spectral dataset of the $\delta$ Orionis Aa binary system. The four observations, obtained with Chandra ACIS HETGS, have a total exposure…
We present a study of the relation between X-rays and ultraviolet emission in quasars for a sample of broad-line, radio-quiet objects obtained from the cross-match of the Sloan Digital Sky Survey DR14 with the latest Chandra Source Catalog…