Related papers: Chandra Orion Ultradeep Project: Observations and …

We present results from X-ray observations of the quadruply lensed quasar RX J0911.4+0551 using data obtained with the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-ray Observatory. The 29 ks observation detects a total of…

We present results of a Chandra observation of a field in NGC 2264. The observations were taken with the ACIS-I camera with an exposure time of 48.1 ks. We present a catalog of 263 sources, which includes X-ray luminosity, optical and…

We present point-source catalogs for the ~2 Ms exposure of the Chandra Deep Field-South (CDF-S); this is one of the two most-sensitive X-ray surveys ever performed. The survey covers an area of ~436 arcmin^2 and reaches on-axis sensitivity…

We present a systematic search for periodic X-ray sources in the bulge of M31, using ~ 2 Ms of archival Chandra observations spanning a temporal baseline of 16 years. Utilizing the Gregory-Loredo algorithm that is designed for…

[Abridged] The central field of the Andromeda galaxy (M 31) has been monitored, using the Chandra HRC-I detector (about 0.1-10 keV energy range) from 2006 to 2012 with the main aim to detect X-rays from optical novae. We present a…

We present here an overview of the status of the Chandra X-ray Observatory which has now been operating for five years. The Observatory is running smoothly, and the scientific return continues to be outstanding. We provide some details on…

We present U, B, V, I broad-band, 6200A TiO medium-band and Halpha photometry of the Orion Nebula Cluster obtained with the WFI imager at the ESO/MPI 2.2 telescope. The nearly-simultaneous observations cover the entire ONC in a field of…

We analyze a ~70 ksec Chandra ACIS-I exposure of the globular cluster Omega Centauri (NGC 5139). The ~17 amin x 17 amin field of view fully encompasses three core radii and almost twice the half-mass radius. We detect 180 sources to a…

We present our results on the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer (ACIS) observations of the bright Oort Cloud comets C/2012 S1 (ISON) and C/2011 L4 (PanSTARRS). ISON was observed between 2013 October 31-November 06…

The source GX 13+1 is a persistent, bright Galactic X-ray binary hosting an accreting neutron star. It shows highly ionized absorption features, with a blueshift of $\sim$ 400 km s$^{-1}$ and an outflow-mass rate similar to the accretion…

We used the High Energy Transmission Grating Spectrometer (HETGS) onboard the Chandra X-ray Observatory to perform two observations, separated by three weeks, of the Orion Trapezium region. The zeroth order images on the Advanced CCD…

We present first results from an X-ray study of the Hubble Deep Field North (HDF-N) and its environs obtained using 166 ks of data collected by the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-ray Observatory. This is the…

We have used the Chandra X-ray Observatory to resolve spatially and spectrally the X-ray emission from the Circinus Galaxy. We report here on the nature of the X-ray emission from the off-nuclear point sources associated with the disk of…

We present results of a sensitive 76 ksec Chandra observation of the young stellar cluster in NGC 2024 (d = 415 pc) in the Orion B giant molecular cloud. Previous infrared observations have shown that this remarkable cluster contains…

We have conducted a systematic study of X-ray emission from ultra-compact dwarf (UCD) galaxies and extended star clusters (ESCs), based on archival {\sl Chandra} observations. Among a sample of 511 UCDs and ESCs complied from the…

In this work we present the results of the survey carried out on one of the deepest X-ray fields observed by the XMM-Newton satellite. The 1.75 Ms Ultra Narrow Deep Field (XMM175UNDF) survey is made by 13 observations taken over 2 years…

The Chandra X-ray Observatory (CXO) was launched on July 23, 1999 and reached its final orbit on August 7, 1999. The CXO is in a highly elliptical orbit, approximately 140,000 km x 10,000 km, and has a period of approximately 63.5 hours (~…

We present a catalog of optical and infrared identifications (ID) of X-ray sources in the AKARI North Ecliptic Pole (NEP) Deep field detected with Chandra covering $\sim 0.34\,{\rm deg^{2}}$ with 0.5-2 keV flux limits ranging $\sim 2…

Modern X-ray telescopes have detected hundreds of thousands of X-ray sources in the universe. However, current methods to classify these sources using the X-ray data themselves suffer problems - detailed X-ray spectroscopy of individual…

Most stellar flares' soft X-ray lightcurves possess a `typical' morphology, which consists of a rapid rise followed by a slow exponential decay. However, a study of 216 of the brightest flares on 161 pre-main sequence stars, observed during…