Related papers: A Chandra Study of the Circinus Galaxy Point-Sourc…

We present a deep search for and analysis of X-ray sources in a sample of dwarf galaxies (M$_{r}$ < -15.5 mag) located within twelve galaxy clusters from the Kapteyn IAC WEAVE INT Cluster Survey (KIWICS) of photometric observations in the…

We present our first results on field X-ray sources detected in a deep, 184.7 ks observation with the ACIS-I camera on Chandra. The observations target the Lynx field of SPICES, and contains three known X-ray-emitting clusters out to…

With 40 ks of Chandra ACIS-S3 exposure, new information on both the starburst and QSO components of the X-ray emission of Markarian 231, an ultraluminous infrared galaxy and Broad Absorption Line QSO, has been obtained. The bulk of the…

We report the discovery of eight X-ray sources with periodic variability in 487 ks of observations of the Galactic center with Chandra. The sources are identified from a sample of 285 objects detected with 100-4200 net counts. Their periods…

[abridged] We investigate the nature of the luminous X-ray source population detected in a (72 ks) Chandra ACIS-S observation of NGC 4038/39, the Antennae galaxies. We derive the average X-ray spectral properties of sources in different…

We analyze 18 sources that were found to show interesting properties of periodicity, very soft spectra and/or large long-term variability in X-rays in our project of classification of sources from the 2XMMi-DR3 catalog but were poorly…

We show with a short Chandra HRC-S exposure that the powerful X-ray source coincident with the nucleus of M33 is unresolved at the highest spatial resolution available to date (0"4). The source flux is variable, doubling during the 5 ks…

We have found compact, near-nuclear X-ray sources in 21 (54\%) of a complete sample of 39 nearby face-on spiral and elliptical galaxies with available ROSAT HRI data. ROSAT X-ray luminosities (0.2 $-$ 2.4 keV) of these compact X-ray sources…

We present 26 point-sources discovered with Chandra within 200" (~20kpc) of the center of the barred supergiant galaxy NGC 1365. The majority of these sources are high-mass X-ray binaries, containing a neutron star or a black hole accreting…

We report optical spectroscopic identifications of 10 hard (2-10 keV) X-ray selected sources discovered by Chandra. The X-ray flux of the sources ranges between 1.5 and 25 x 10-14 cgs, the lower value being 3 times fainter than in previous…

We present near-infrared long-slit spectra of eight optically-dim X-ray sources obtained with ISAAC on the Very Large Telescope. Six of the sources have hard X-ray emission with a significant fraction of the counts emerging above 2 keV. All…

We report on a deep XMM-Newton EPIC observation of the globular cluster Omega Cen performed on August 13th, 2001. We have detected 11 and 27 faint X-ray sources in the core and half mass radii, searching down to a luminosity of 1.3 x…

We present an X-ray study of the massive edge-on Sa galaxy, Sombrero (M~104; NGC 4594), based on XMM-Newton and Chandra observations. A list of 62 XMM-Newton and 175 Chandra discrete X-ray sources is provided. At energies above 2 keV, the…

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…

Aims. We analyzed multi-epoch X-ray data of the Ultraluminous X-ray source (ULX) NGC 5055 X-1, with luminosity up to $2.32\times10^{40}\ \rm erg\ s^{-1}$, in order to constrain the physical parameters of the source. Methods. We performed…

We present a detailed analysis of XMM archival data of two Ultraluminous X-ray Sources (ULXs) in the nearby spiral galaxy NGC 1313: NGC 1313 X-1 and X-2. The spectral continuum of these sources was modeled with a soft thermal component plus…

The nearby barred spiral galaxy NGC 1313 has been observed with the PSPC instr- ument on board the ROSAT X-ray satellite. Ten individual sources are found. Three sources (X-1, X-2 and X-3 [SN~1978K]) are very bright (~10^40 erg/s) and are…

The 13hr XMM-Newton/Chandra deep survey is the first of two extremely deep XMM-Newton fields observed by the XMM-OM consortium. A 120 ks Chandra mosaic, covering 0.2 square degrees, provides sensitive, confusion-free point source detection…

We present the results of a 17 ks Chandra ACIS-S observation of the nearby dwarf spiral galaxy NGC 4395. Chandra affords the first high-quality, broadband X-ray detection of the active nucleus of this object that is uncontaminated by nearby…

We present the results of a 17 ks Chandra observation of the nearby dwarf spiral galaxy NGC 4395, focusing on the X-ray properties of the moderate-mass black hole that resides in its nucleus. Chandra affords the first high-quality,…