Related papers: The distribution of AGN in a large sample of galax…

The Chandra data archive after eight years' accumulation is a treasure for various studies, and in this paper we exploit this valuable resource to study the X-ray point source populations in nearby galaxies. By December 14, 2007, 383…

We present a systematic search for extraplanar X-ray point sources around 19 late-type, highly inclined disk galaxies residing in the Virgo cluster, based on archival Chandra observations reaching a source detection sensitivity of…

We present a statistical analysis of the Chandra observation of the source field around the 3C 295 galaxy cluster (z=0.46) aimed at the search for clustering of X-ray sources. We applied three different methods of analysis, all suggesting a…

We present an X-ray and optical analysis of a 2-8 keV flux limited (fx > 10e-14 erg s^-1 cm^-2) sample of 126 AGN detected in 16 Chandra fields. This work represents a small though significant subset of the Chandra Multiwavelength Project…

Using the Chandra Advanced CCD Imaging Spectrometer Imaging array (ACIS-I), we have carried out a deep hard X-ray observation of the Galactic plane region at (l,b) ~ (28.5, 0.0), where no discrete X-ray source had been reported previously.…

Most galaxies in clusters have supermassive black holes at their center, and a fraction of those supermassive black holes show strong activity. These active galactic nuclei(AGNs) are an important probe of environmental dependence of galaxy…

We discuss the optical properties, X-ray detections, and Active Galactic Nucleus (AGN) populations of four clusters at z ~ 1 in the Subaru-XMM Deep Field (SXDF). The velocity distribution and plausible extended X-ray detections are…

The features and make up of the population of X-ray sources in Galactic star clusters reflect the properties of the underlying stellar environment. Cluster age, mass, stellar encounter rate, binary frequency, metallicity, and maybe other…

The X-ray luminosity function (XLF) of galaxies is dominated by AGN (classified by their optical spectra) above Lx=10**42 erg/s, below this value by normal galaxies. The X-ray flux of AGN at low X-ray luminosity therefore contains…

We present the X-ray spectra of 86 optically-identified sources in the 13H XMM-Newton/Chandra deep field which have >70 X-ray counts. The sample consists of 50 broad line AGN, 25 narrow emission line galaxies, 6 absorption line galaxies,…

The first systematic study of the serendipitous X-ray source density around 10 high z (0.24<z<1.2) clusters has been performed with Chandra. A factor ~2 overdensity has been found in 4 cluster fields, increasing to 11 the number of known…

We present the statistical evaluation of a count rate and area limited complete sample of the ROSAT All-Sky Survey (RASS) comprising 674 sources. The RASS sources are located in six study areas outside the galactic plane (|b^II| >= 20 deg)…

We present a survey of X-ray point sources in a 91 ksec Chandra ACIS-S observation of the z=0.83 cluster MS1054-0321. We detect 47 X-ray sources within the 8.3 arcmin by 8.3 arcmin field, of which two are immediately confirmed from…

We carry out classification of 4330 X-ray sources in the 2XMMi-DR3 catalog. They are selected under the requirement of being a point source with multiple XMM-Newton observations and at least one detection with the signal-to-noise ratio…

We develop a new diagnostic method to classify galaxies into AGN hosts, star-forming galaxies, and absorption-dominated galaxies by combining the [O III]/Hbeta ratio with rest-frame U-B color. This can be used to robustly select AGNs in…

We use archival Chandra X-ray Observatory data to investigate X-ray emission from early-type galaxies in the rich z=0.06 cluster Abell 3128. By combining the X-ray count-rates from an input list of optically-selected galaxies, we obtain a…

We find that X-ray sources in the Extended Chandra Deep Field South are strongly spatially correlated with LABOCA 870 micron sources. We investigate the dependence of this correlation on X-ray flux, hardness ratio and column density,…

We measure the clustering of non-quasar X-ray AGN at z=0.7-1.4 in the AEGIS field. Using the cross-correlation of 113 Chandra-selected AGN, with a median log L_X=42.8 erg s^-1, with ~5,000 DEEP2 galaxies, we find that the X-ray AGN are fit…

We report the multi-wavelength properties of millimeter galaxies hosting X-ray detected active galactic nuclei (AGNs) from the ALMA Lensing Cluster Survey (ALCS). ALCS is an extensive survey of well-studied lensing clusters with ALMA,…

Our goal is to characterize AGN populations by comparing their X-ray and optical classifications. We present a sample of 99 spectroscopically identified X-ray point sources in the XMM-LSS survey which are significantly detected in the…