Related papers: Localizing INTEGRAL Sources with Chandra: X-Ray an…

We combine infrared spectra in the I, J, H and K bands together with JHK photometry to characterize the spectral type, luminosity class and distance to the infrared counterparts to five INTEGRAL sources. For SAX J18186-1703 and IGR…

Using 2.5 Ms of data obtained by the INTEGRAL satellite in 2003-2004, we discovered persistent hard X-ray emission from the soft gamma-ray repeater SGR 1900+14. Its 20-100 keV spectrum is well described by a steep power law with photon…

We review highlights of the results obtained from recent Galactic X-ray survey observations, in particular ASCA Galactic center and plane survey and our Chandra deep survey on the (l,b)=(28.5,0) region. Strong hard X-ray diffuse components…

We present new Chandra observations that complete a sample of seventeen (17) luminous infrared galaxies (LIRGs) with D < 60 Mpc and low Galactic column densities of N_H < 5 X 10^20 cm^-2. The LIRGs in our sample have total infrared…

In a recent paper, Romero et al. (1999) have presented the results of a positional correlation analysis of the low-latitude unidentified gamma-ray sources in the Third EGRET catalog with complete lists of galactic objects like supernova…

We examine the properties of the X-ray detected, Infrared Excess AGN or Dust Obscured Galaxies (DOGs) in the Chandra Deep Fields (CDF). We find 26 X-ray selected sources which obey the 24 micron to R-band flux ratio criterion f_24/f_R>1000.…

As a part of the ISOPHOT CIRB (Cosmic Infrared Background Radiation) project we have searched for point-like sources in eight fields mapped at two or three wavelengths between 90 and 180um. Most sources are previously unknown and based on…

We present a catalog of 9017 X-ray sources identified in Chandra observations of a 2 by 0.8 degree field around the Galactic center. We increase the number of known X-ray sources in the region by a factor of 2.5. The catalog incorporates…

We present optical spectra and near-infrared imaging of a sample of serendipitous X-ray sources detected in the field of Chandra observations of the A2390 cluster of galaxies. The sources have 0.5-7 keV fluxes of 0.6-8 x 10^{-14} erg…

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,…

IGR J17091-3624 was discovered in 2003 April by INTEGRAL/IBIS during its Galactic Centre Deep Exposure programme. The source was initially detectable only in the 40--100 keV range, but after two days was also detected in the 15-40 keV…

We derive the spectra of the cosmic X-ray background (CXB) and of the Galactic ridge X-ray emission (GRXE) in the ~20-200 keV range from the data of the IBIS instrument aboard the INTEGRAL satellite obtained during the four dedicated…

We present the X-ray spectral analysis of the 390 brightest extragalactic sources in the Chandra-COSMOS catalog, showing at least 70 net counts in the 0.5-7 keV band. This sample has a 100% completeness in optical-IR identification, with…

The determination of the broad (0.1-100 keV) spectra of active galaxies is crucial for understanding and discriminating among emission models, for estimating the properties of the Comptonising/reflecting region around the central black hole…

We present the analysis of serendipitous sources in a deep, 500 ksec, hard X-ray observation of the Coma cluster region with the IBIS instrument onboard INTEGRAL. In addition to the Coma cluster, the final 20-50 keV image contains 12…

We present the results obtained from a comprehensive timing and spectral study of two high-mass X-ray binary sources using NuSTAR observations. These two sources, IGR J16320-4751 and IGR J16479-4514, were discovered by INTEGRAL and have…

We briefly report here on our ongoing X-ray spectroscopy and variability analyses of 136 faint X-ray sources discovered in the 2 Ms Chandra Deep Field North observations spanning 1.4x10-15 to 2x10-13 ergs s-1 cm-2. Most sources are…

The results of Chandra snapshot observations of 11 LINERs (Low-Ionization Nuclear Emission-line Regions), three low-luminosity Seyfert galaxies, and one HII-LINER transition object are presented. Our sample consists of all the objects with…

Parameters from the literature, such as positions, photoelectric absorption (nH), spin and orbital periods, and distances or redshifts, were collected for all ~500 sources detected by INTEGRAL-ISGRI so far. We investigate where new and…

We present results of our Chandra observation with the ACIS-I instrument centered on the position of Sagittarius A* (Sgr A*), the compact nonthermal radio source associated with the massive black hole (MBH) at the dynamical center of the…