Related papers: Chandra deep X-ray observation on the Galactic pla…
We present the first results of a wide area X-ray survey within the Sloan Digital Sky Survey (SDSS) Stripe 82, a 300 deg$^2$ region of the sky with a substantial investment in multi-wavelength coverage. We analyzed archival {\it Chandra}…
With the superb angular resolution of the Chandra Observatory, it is now possible to detect X-ray point sources, either embedded in galaxy clusters or along the cluster line of sight, which could not be resolved by previous instruments.…
We report the results of identification of 8 hard X-ray sources discovered by the INTEGRAL observatory during the ongoing all-sky survey. These sources have been observed by Chandra. In 6 cases a bright X-ray source was found within the…
We present X-ray point-source catalogs for a deep 400 ks Chandra ACIS-I exposure of the SSA22 field. The observations are centred on a z = 3.09 protocluster, which is populated by Lyman break galaxies (LBGs), Lyalpha emitters (LAEs), and…
Apparently diffuse X-ray emission has been known to exist along the central quarter of the Galactic Plane since the beginning of the X-ray astronomy, which is referred to as the Galactic Ridge X-ray emission (GRXE). Recent deep X-ray…
We present the first results from 60ks of observations of Arp 220 using the ACIS-S instrument on Chandra. We report the detection of several sources near the galaxy's nucleus, including a point source with a hard spectrum that is coincident…
We report results of a serendipitous hard X-ray (3--20 keV), nearly all-sky (|b|>10deg) survey based on RXTE/PCA observations performed during satellite reorientations in 1996--2002. The survey is 80% (90%) complete to a 4$\sigma$ limiting…
We present the first results of the Chandra and optical follow-up observations of hard X-ray sources detected in the ASCA Medium Sensitivity Survey (AMSS). Optical identifications are made for five objects. Three of them show either weak or…
Previous studies suggest that the Galactic diffuse X-ray emission is composed of unresolved point sources, primarily mCVs. However, nearby mCVs have a much lower 6.7 keV line equivalent width ($\rm EW_{6.7}$) compared to the diffuse X-ray…
The COSMOS-Legacy survey is a 4.6 Ms Chandra program that has imaged 2.2 deg$^2$ of the COSMOS field with an effective exposure of $\simeq$160 ks over the central 1.5 deg$^2$ and of $\simeq$80 ks in the remaining area. The survey is the…
We present the results of optical spectroscopic identifications of a bright subsample of 2-10keV hard X-ray selected sources from the ASCA Medium Sensitivity Survey in the northern sky. The flux limit of the subsample is 3*10^-13 erg s^-1…
We present an exploratory Chandra ACIS-S3 study of the diffuse component of the Cosmic X-ray Background in the 0.3-7 keV band for four directions at high Galactic latitudes, with emphasis on details of the ACIS instrumental background…
We present results from a 221.9 ks Chandra exposure of the HDF-N and its vicinity, concentrating on the 8.6' X 8.7' area covered by the Caltech Faint Field Galaxy Redshift Survey (the `Caltech area'). The minimum detectable fluxes in the…
We present a search for nuclear X-ray emission in the brightest cluster galaxies (BCGs) of a sample of groups and clusters of galaxies extracted from the Chandra archive. The exquisite angular resolution of Chandra allows us to obtain…
We present an analysis of two deep (75 ks) Chandra observations of the European Large Area ISO Survey (ELAIS) fields N1 and N2 as the first results from the ELAIS deep X-ray survey. This survey is being conducted in well studied regions…
We have investigated the X-ray spectral properties of a sample of 138 X-ray sources detected serendipitously in $XMM-Newton$ observations of the Galactic plane, at an intermediate to faint flux level. We divide our sample into 5 subgroups…
The Serendipitous Extragalactic X-ray Source Identification (SEXSI) Program is designed to extend greatly the sample of identified extragalactic hard X-ray 2-10 keV sources at intermediate fluxes ($\sim 10^{-13} - 10^{-15} erg/cm2/s$).…
Models for the origin of the hard X-ray background have suggested that sources with the most accretion activity lie hidden in highly obscured AGN. We report on our study of hard, serendipitous sources in the fields of Chandra clusters with…
We present an 82 ksec Chandra ACIS-I observation of a large-scale hierarchical complex, which consists of various clusters/groups of galaxies and low-surface brightness X-ray emission at z = 0.247. This high-resolution {\sl Chandra}…
The NuSTAR serendipitous survey has already uncovered a large number of Active Galactic Nuclei (AGN), providing new information about the composition of the Cosmic X-ray Background. For the AGN off the Galactic plane, it has been possible…