Search Publications
INTEGRAL/IBIS nine-year Galactic hard X-ray survey
Sunyaev, R.; Krivonos, R.; Tsygankov, S. +3 more
Context. The INTEGRAL observatory operating in a hard X-ray/gamma domain has gathered a large observational data set over nine years starting in 2003. Most of the observing time was dedicated to the Galactic source population study, making possible the deepest Galactic survey in hard X-rays ever compiled.
Aims: We aim to perform a Galactic su…
The first INTEGRAL-OMC catalogue of optically variable sources
Mas-Hesse, J. M.; Domingo, A.; Alfonso-Garzón, J. +1 more
Context. The Optical Monitoring Camera (OMC) onboard INTEGRAL provides photometry in the Johnson V-band. With an aperture of 50 mm and a field of view of 5° × 5°, OMC is able to detect optical sources brighter than V ~ 18, from a previously selected list of potential targets of interest. After more than nine years of observations, the OMC database…
Multiwavelength campaign on Mrk 509. VIII. Location of the X-ray absorber
Kaastra, J. S.; Kriss, G. A.; Arav, N. +14 more
Aims: More than half of all active galactic nuclei show strong photoionised outflows. A major uncertainty in models for these outflows is the distance of the gas to the central black hole. We use the results of a massive multiwavelength monitoring campaign on the bright Seyfert 1 galaxy Mrk 509 to constrain the location of the outflow compone…
XMM-Newton observation of 4U 1820-30. Broad band spectrum and the contribution of the cold interstellar medium
Waters, L. B. F. M.; Kaastra, J. S.; Costantini, E. +6 more
We present an analysis of the bright X-ray binary 4U 1820-30, thet is based mainly on XMM-Newton-RGS data, in addition to complementary data from XMM-Newton-EPIC-pn, INTEGRAL, and Chandra-HETG, to investigate different aspects of the source. The broad band continuum is fitted well by a classical combination of black body and Comptonized emission. …
Outburst of GX 304-1 monitored with INTEGRAL: positive correlation between the cyclotron line energy and flux
Klochkov, D.; Santangelo, A.; Wilms, J. +10 more
Context. X-ray spectra of many accreting pulsars exhibit significant variations as a function of flux and thus of mass accretion rate. In some of these pulsars, the centroid energy of the cyclotron line(s), which characterizes the magnetic field strength at the site of the X-ray emission, has been found to vary systematically with flux.
Aims:…
Characterization of new hard X-ray cataclysmic variables
Mukai, K.; de Martino, D.; Masetti, N. +5 more
Aims: We aim at characterizing a sample of nine new hard X-ray selected cataclysmic variable (CVs), to unambiguously identify them as magnetic systems of the intermediate polar (IP) type.
Methods: We performed detailed timing and spectral analysis by using X-ray, and simultaneous UV and optical data collected by XMM-Newton, complemented …
Multi-color observations of short GRB afterglows: 20 events observed between 2007 and 2010
Greiner, J.; McBreen, S.; Hartmann, D. H. +18 more
We report on follow-up observations of 20 short-duration gamma-ray bursts (GRBs; T90 < 2 s) performed in g'r'i'z'JHKs with the Gamma-Ray Burst Optical Near-Infrared Detector (GROND) between mid-2007 and the end of 2010. This is one of the most comprehensive data sets on GRB afterglow observations of short bursts published …
Spin period evolution of GX 1+4
Kretschmar, P.; Kuulkers, E.; Larsson, S. +4 more
Aims: We aim both to complement the existing data on the spin history of the peculiar accreting X-ray pulsar GX 1+4 with more past and current data from BeppoSAX, INTEGRAL, and Fermi and to interpret the evolution in the framework of accretion theory.
Methods: We used source light curves obtained from BeppoSAX/WFC and INTEGRAL/ISGRI to d…
The hard X-ray emission of X Persei
Santangelo, A.; Doroshenko, V.; Kreykenbohm, I. +1 more
We present an analysis of the spectral properties of the peculiar X-ray pulsar
Unveiling the nature of INTEGRAL objects through optical spectroscopy. IX. Twenty two more identifications, and a glance into the far hard X-ray Universe
Palazzi, E.; Minniti, D.; Masetti, N. +14 more
Since its launch in October 2002, the INTEGRAL satellite has revolutionized our knowledge of the hard X-ray sky thanks to its unprecedented imaging capabilities and source detection positional accuracy above 20 keV. Nevertheless, many of the newly-detected sources in the INTEGRAL sky surveys are of unknown nature. The combined use of available inf…