Related papers: Optical identification of hard X-ray source IGRJ18…
IRAS 00521$-$7054 is the first Seyfert 2 in which the presence of an extremely large Fe K$\alpha$ line has been claimed. We report here on the analysis of a 100 ks Suzaku observation of the source. We confirm the existence of a very strong…
Details of the discovery of a new X-ray source, IGR J18462-0223, on October 12, 2007, during a short (several hours), intense (~ 35 mCrab at the peak) outburst of hard radiation by the IBIS/ISGRI gamma-ray telescope onboard the INTEGRAL…
The hard X-ray sensitivity and arcminute position accuracy of the recently launched International Gamma-Ray Laboratory (INTEGRAL) has lead to the (re-)discovery of a class of heavily absorbed hard X-ray sources lying in the Galactic plane.…
The INTEGRAL satellite, during its regular scanning observations of the Galactic plane, has discovered several new X-ray sources emitting above 20 keV. The nature of the great majority of them is still unknown. Here we report on the likely…
We observed 7 INTEGRAL sources with the Chandra X-ray Observatory to refine their localization to ~2 arcsec and to study their X-ray spectra. Two sources are inferred to have a Galactic origin: IGR J08390-4833 is most likely a magnetic…
(abridged) We analysed data from observations of 17 INTEGRAL sources made with the Swift satellite. We refine the position of the hard X-ray sources to an accuracy of a few arcsec. We then browsed the online catalogs (e.g., NED, SIMBAD,…
(Abridged) We made use of X-ray observations with the X-ray telescope on-board the \swift observatory to refine the X-ray position to 3-5" accuracy of 12 INTEGRAL sources, so as to further identify their counterpart at optical, infrared,…
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) is discovering a large number of new hard X-ray sources, many of them being HMXBs. The identification and spectral characterization of their optical/infrared counterparts is a…
We studied the soft-X-ray emission of five hard-X sources: IGR J08262-3736, IGR J17354-3255, IGR J16328-4726, SAX J1818.6-1703 and IGR J17348-2045. These sources are: a confirmed supergiant high mass X-ray binary (IGR J08262-3736);…
New high variability extragalactic sources may be identified by comparing the flux of sources seen in the XMM-Newton Slew Survey with detections and upper limits from the ROSAT All Sky Survey. In November 2012, X-ray emission was detected…
The Ibis/Isgri imager on Integral detected for the first time a hard X-ray source, IGR J17456-2901, located within 1' of Sgr A* over the energy range 20-100 keV. Here we present the results of a detailed analysis of ~7 Ms of Integral…
We present the results of our optical identifications of four hard X-ray sources from the Swift all-sky survey. We obtained optical spectra for each of the program objects with the 6-m BTA telescope (Special Astrophysical Observatory,…
In this paper we report the discovery of an hard X-ray selected Type 2 Seyfert galaxy and we present and discuss its X-ray and optical spectrum together with the radio to X-ray energy distribution. The X-ray source - AXJ2254+1146 - is part…
The IRAM interferometer has been used to detect the submm source HDF 850.1 found by Hughes et al. (1998) in the Hubble Deep Field. The flux density measured at 1.3mm is 2.2 mJy, in agreement with the flux density measured at the JCMT. The…
Aims: We reanalyse optical spectra of the z=6.7 gamma-ray burst GRB 080913, adding hitherto unpublished spectra, in order to reassess the measurement of the neutral fraction of the IGM at high redshifts. Methods: In the data reduction we…
We discuss the hard X-ray properties of the Seyfert galaxy Ton S 180, based upon the analysis of ASCA data. We find the X-ray flux varied by a factor ~2 on a time scale of a few thousand seconds. The source showed significantly higher…
We present Chandra and XMM-Newton observations of the composite star-forming/Seyfert galaxy IRAS20051-1117. The X-ray imaging and spectral properties reveal the presence of an active nucleus. The Chandra image shows a strong nuclear point…
We report on the results of observations of hard X-ray sources in the Galactic plane with the Chandra X-ray Observatory. The hard X-ray IGR sources were discovered by the INTEGRAL satellite, and the goals of the Chandra observations are to…
High mass X-ray binaries hosting red supergiant (RSG) donors are a rare but crucial phase in massive stellar evolution, with only one source previously known in the Milky Way. In this letter, we present the identification of the second…
The observation of the Narrow-Line Seyfert 1 galaxy IRAS13349+2438 performed by XMM-Newton European Photon Imaging Camera between 0.3-10 keV, is presented here. The broadband spectrum of the source is dominated at low energies (E < 2 keV)…