Related papers: Hard X-ray observations of Extremely Red Objects

We have observed the Orion Molecular Clouds 2 and 3 (OMC-2 and OMC-3) with the Chandra X-ray Observatory (CXO). The northern part of OMC-3 is found to be particularly rich in new X-ray features; four hard X-ray sources are located in and…

Using the Chandra ACIS-I instruments, we have carried out a deep X-ray observation on the Galactic plane region at (l,b) ~ (28.5, 0.0), where no discrete X-ray sources have been known previously. We have detected, as well as strong diffuse…

We define a sample of 27 radio-excess AGN in the Chandra Deep Field North by selecting galaxies that do not obey the radio/infrared correlation for radio-quiet AGN and star-forming galaxies. Approximately 60% of these radio-excess AGN are…

In this paper we investigate the properties of low X-ray-to-optical flux ratio sources detected in a wide area (2.5deg^2) shallow (f(0.5-8keV)~10e-14cgs) XMM-Newton survey. We find a total of 26 sources (5% of the total X-ray selected…

The COSMOS survey is a multiwavelength survey aimed to study the evolution of galaxies, AGN and the large scale structure. The XMM-COSMOS is a deep X-ray survey over the full 2 deg2 of the COSMOS area. It consists of 55 XMM-Newton pointings…

Recent Chandra and XMM-Newton surveys have uncovered a large fraction of the obscured AGN responsible of the hard X-ray background. One of the most intriguing results of extensive programs of follow-up observations concerns the optical and…

Ultraluminous and hyperluminous X-ray sources (ULXs and HLXs) are among the brightest astrophysical objects in the X-ray sky. While ULXs most likely host stellar-mass compact objects accreting at super-Eddington rates, HLXs are compelling…

We present new estimates on the fraction of heavily X-ray obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift of $z \leq$ 0.8. From a sample of 540 AGNs selected by mid-IR (MIR) properties in observed X-ray survey…

We present the results of a survey for Extremely Red Objects (EROs) in the fields of ten galaxy cluster lenses at z~0.2, combining high-resolution Hubble Space Telescope imaging with deep K-band imaging from UKIRT. We detect 60 EROs with…

We present a sample of twenty-one ROSAT bright active galactic nuclei (AGN), representing a range of spectral classes, and selected for follow-up snap-shot observations with XMM-Newton. The typical exposure was between 5-10 ks. The objects…

We use observations from the 9 square degree multiwavelength survey in Bootes to identify hundreds of obscured active galactic nuclei (AGN) with high redshifts (z > 0.7), luminosities (L_bol > 10^45 ergs/s), and moderate obscuring columns…

We present the spectral energy distributions (SEDs) of a hard X-ray selected sample. The sample contains 136 sources with F(2-10 keV)>10^-14 erg/cm^2/s and 132 are AGNs. The sources are detected in a 1 square degree area of the…

Galactic X-ray sources are diverse, ranging from active M dwarfs to compact object binaries, and everything in between. The X-ray landscape of today is rich, with point source catalogs such as those from XMM-Newton, Chandra, and Swift, each…

In order to find the most extreme dust-hidden high-redshift galaxies, we select 196 extremely red objects in the Ks and IRAC bands (KIEROs, [Ks-4.5um](AB)>1.6) in the 0.06 deg^2 GOODS-N region. This selection avoids the Balmer breaks of…

Deep X-ray surveys have shown that the cosmic X-ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80% of the 0.1-10 keV X-ray…

Using high-resolution HST/Wide Field Camera 3 F125W imaging from the CANDELS-COSMOS field, we report the the structural and morphological properties of Extremely Red Objects (EROs) at $z\sim1$. Based on the UVJ color criteria, we separate…

We performed deep K'-band imaging observations of 2 massive clusters, MS 0451.6-0305 at z = 0.55 and MS 0440.5+0204 at z = 0.19, for searching counterparts of the faint sub-mm sources behind these clusters, which would provide one of the…

We present the results of a systematic analysis of the XMM-Newton spectra of nearby optically bright QSOs. The objects have been selected from X-ray Galaxy Catalog Xgal20. It is a catalog of 1172 manually identified and classified galaxies,…

Using U'- through Ks-band imaging data in the GOODS-South field, we construct a large, complete sample of 275 ``extremely red objects'' (EROs; K_s<22.0, R-K_s>3.35; AB), all with deep HST/ACS imaging in B_435, V_606, i_775, and z_850, and…

The spectrum of the hard X-ray background records the history of accretion processes integrated over the cosmic time. Several observational and theoretical evidences indicate that a significant fraction of the energy density is obscured by…