Related papers: The Luminous X-ray Source Population in M51 Observ…

A deep (98.2 ks) Chandra Cycle-1 observation has revealed a wealth of discrete X-ray sources as well as diffuse emission in the nearby face-on spiral galaxy M101. From this rich dataset we have created a catalog of the 110 sources from the…

(Abridged) We conducted a Chandra ACIS observation of the nearby Sculptor Group Sd galaxy NGC 7793. At the assumed distance to NGC 7793 of 3.91 Mpc, the limiting unabsorbed luminosity of the detected discrete X-ray sources (0.2-10.0 keV) is…

Recent observations of galaxies continue to reveal new ultraluminous X-ray sources (ULXs), increasing their known population and improving the statistics needed to understand their nature. We study the ULX populations of NGC 4631 and NGC…

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 the detailed analysis of the X-ray properties of the discrete sources detected in a long (72 ks) \chandra ACIS-S observation of the Antennae galaxies. We detect 49 sources, down to a detection limit of ~ 10^{38} erg\s; 18 sources…

We present an analysis of 15 Chandra observations of the nearby spiral galaxy M81 taken over the course of six weeks in May--July 2005. Each observation reaches a sensitivity of ~10^37 erg/s. With these observations and one previous deeper…

We study the X-ray and optical properties of the ultraluminous X-ray source (ULX) X-6 in the nearby galaxy NGC 4258 (M106) based on the archival {\it XMM-Newton}, {\it Chandra}, {\it Swift}, and {\it Hubble Space Telescope} ({\it HST})…

We analyse all the available Chandra observations of the Cartwheel Galaxy and its compact group, taken between 2001 and 2008, with the main aim of addressing the variability in the X-ray band for this spectacular collisional ring galaxy. We…

We present radio through X-ray results of a bright (10^{40} erg/s in the 0.5 to 8.0 keV band) ultraluminous X-ray source (ULX), CXOU J153434.9+151149, in the starburst, interacting pair of galaxies NGC 5953/5954. Chandra image of this ULX…

VLT images in $BVI$ are used to identify the optical counterparts to bright CHANDRA X-ray points sources discovered by Kraft et al. (2001, ApJ, 560, 675) in NGC5128. Of a total of 111 X-ray point sources with L_X>2*10^{36} ergs/s present in…

A previously undetected X-ray source (L_X<10**36 erg/s) in the strongly star-forming galaxy M83 entered an ultraluminous state between August 2009 and December 2010. It was first seen with Chandra on 23 December 2010 at L_X ~ 4 10**39…

We use a set of conservative criteria to identify luminous supersoft X-ray sources(SSSs) in external galaxies. We test this approach on blackbody models, and then apply it to {\it Chandra} data from 4 galaxies: an elliptical (NGC 4967), 2…

We report on the {\it Chandra} observations of the elliptical galaxy NGC 1399, concentrating on the X-ray sources identified with globular clusters (GCs). A large fraction of the 2-10 keV X-ray emission in the $8' \times 8'$ {\it Chandra}…

The more than 80 nearby galaxies imaged with the Chandra Advanced CCD Imaging Spectrometer have been analyzed in a search for Ultra-Luminous X-ray (ULX) sources. The sample of galaxies span the range of Hubble morphological types and…

We present the results of a complete spectral survey of the X-ray point sources detected in five XMM-Newton observations along the major axis of M31 but avoiding the central bulge, aimed at establishing the population characteristics of…

We present highlights from a study of a sample of 10 extreme-luminosity candidate ultraluminous X-ray sources (L_X > 5 x 10^(40) erg sec^(-1)), all at distances < 100 Mpc, identified from a cross-correlation of the RC3 catalogue of galaxies…

Using the Chandra Source Catalog 2.0 and a newly compiled catalogue of galaxies in the local Universe, we deliver a census of ultraluminous X-ray source (ULX) populations in nearby galaxies. We find 629 ULX candidates in 309 galaxies with…

The population of low-luminosity (< 10^35 erg/s) X-Ray Binaries (XRBs) has been investigated in our Galaxy and M31 but not further. To address this problem, we have used data from the Chandra X-Ray Observatory and the Hubble Space Telescope…

We present results from a Chandra study of ultraluminous X-ray sources (ULXs) in a sample of 17 nearby (D_L<60 Mpc) luminous infrared galaxies (LIRGs), selected to have star formation rates (SFRs) in excess of 7 M_sun yr^-1 and low…

This study represents the most sensitive Chandra X-ray point source catalogue of M31. Using 133 publicly available Chandra ACIS-I/S observations totalling ~1 Ms, we detected 795 X-ray sources in the bulge, northeast, and southwest fields of…