Related papers: Hunting for High-Mass X-ray Binaries in the Galact…
We present the first survey results of hard X-ray point sources in the Galactic Center (GC) region by NuSTAR. We have discovered 70 hard (3-79 keV) X-ray point sources in a 0.6 deg^2 region around Sgr A* with a total exposure of 1.7 Ms, and…
The Nuclear Spectroscopic Telescope Array (NuSTAR) provides an improvement in sensitivity at energies above 10 keV by two orders of magnitude over non-focusing satellites, making it possible to probe deeper into the Galaxy and Universe.…
We searched for infrared counterparts to the cluster of X-ray point sources discovered by Chandra in the Galactic Center Region (GCR). While the sources could be white dwarfs, neutron stars, or black holes accreting from stellar companions,…
We present a catalog of 5184 candidate infrared counterparts to X-ray sources detected towards the Galactic center. The X-ray sample contains 9017 point sources detected in this region by the Chandra X-ray Observatory, including data from a…
The Chandra X-ray Observatory has now discovered nearly 10,000 X-ray point sources in the 2 x 0.8 degree region around the Galactic Center (Muno 2009). The sources are likely to be a population of accreting binaries in the Galactic Center,…
Nearby galaxy surveys have long classified X-ray binaries (XRBs) by the mass category of their donor stars (high-mass and low-mass). The NuSTAR observatory, which provides imaging data at E $>10$ keV, has enabled the classification of…
We present an updated catalog of X-ray point sources in the inner 500$\arcsec$ ($\sim$20 parsec) of the Galactic Center (GC), where the {\it nuclear star cluster} (NSC) stands, based on a total of $\sim$4.5 Ms of {\it Chandra} observations…
We identify sources with extremely hard X-ray spectra (i.e., with photon indices of Gamma<0.6 in the 13 sq. deg. NuSTAR serendipitous survey, to search for the most highly obscured AGNs detected at >10 keV. Eight extreme NuSTAR sources are…
We present the results of a Chandra/HST study of the point sources of the NGC 4472. We identify 144 X-ray sources, 72 with HST matches. The optical data show 1102 sources, 829 with globular cluster colors. Thirty matches are found - likely…
We present results from a 34 ks Chandra/ACIS-S observation of the nearby (d=3.1 Mpc) lenticular galaxy NGC 5102, previously shown to have an unusually low X-ray luminosity. We detect eleven X-ray point sources within the the $D_{25}$…
We present 15 high mass X-ray binary (HMXB) candidates in the disk of M31 for which we are able to infer compact object type, spectral type of the donor star, and age using multiwavelength observations from NuSTAR, Chandra, and the Hubble…
We report on the first ten identifications of sources serendipitously detected by the NuSTAR to provide the first sensitive census of the cosmic X-ray background (CXB) source population at >10 keV. We find that these NuSTAR-detected sources…
We have conducted a near-infrared spectroscopic survey of 47 candidate counterparts to X-ray sources discovered by the Chandra X-ray Observatory near the Galactic Center (GC). Though a significant number of these astrometric matches are…
High-mass X-ray binaries (HMXBs) are a particular class of high-energy sources that require multi-wavelength observational efforts to be properly characterised. New identifications and the refinement of previous measurements are regularly…
We have carried out an in-depth study of low-mass X-ray binaries (LMXBs) detected in the nearby lenticular galaxy NGC 3115, using the Megasecond Chandra X-Ray Visionary Project observation (total exposure time 1.1 Ms). In total we found 136…
The NuSTAR Legacy program 'Unidentified INTEGRAL sources' targeted faint hard X-ray sources revealed by INTEGRAL in the Galactic plane in order to provide conclusive identification of their nature and insights on the population of faint…
We investigated the X-ray spectral properties of a collection of low-mass X-ray binaries (LMXBs) within a sample of 15 nearby early-type galaxies observed with Chandra. We find that the spectrum of the sum of the sources in a given galaxy…
We have detected 523 sources in a survey of the Small Magellanic Cloud (SMC) Wing with Chandra. By cross-correlating the X-ray data with optical and near-infrared catalogues we have found 300 matches. Using a technique that combines X-ray…
Our neighbouring large spiral galaxy, the Andromeda galaxy (M 31 or NGC 224), is an ideal target to study the X-ray source population of a nearby galaxy. NuSTAR observed the central region of M 31 in 2015 and allows studying the population…
We present a catalog of hard X-ray sources in a square-degree region surveyed by NuSTAR in the direction of the Norma spiral arm. This survey has a total exposure time of 1.7 Ms, and typical and maximum exposure depths of 50 ks and 1 Ms,…