Details

Autor(en) / Beteiligte

• Landi, R.
• Bassani, L.
• Bazzano, A.
• Bird, A. J.
• Fiocchi, M.
• Malizia, A.
• Panessa, F.
• Sguera, V.
• Ubertini, P.

Titel

Investigating the X-ray counterparts to unidentified sources in the 1000-orbit INTEGRAL/IBIS catalogue

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2017-08, Vol.470 (1), p.1107-1120

Ort / Verlag

Oxford University Press

Erscheinungsjahr

2017

Quelle

The Electronic Journals Library

Beschreibungen/Notizen

• Abstract The latest INTEGRAL/IBIS all-sky survey lists 219 hard X-ray sources whose nature is still unknown. We report on our ongoing campaign aimed at identifying these high-energy emitters by exploiting the focusing capabilities of the X-ray Telescope (XRT, 0.2–10 keV) onboard Swift, which allow an enhancement of the source localization to arcsec level, thus facilitating the identification of the likely counterpart. By cross-correlating the list of the unidentified IBIS sources included in the latest IBIS catalogue with Swift/XRT archival data, we found a set of 14 objects, not yet reported in the literature, for which XRT data were available. We found no detection in only one case, a single X-ray association in nine sources and 2/3 associations in the remaining objects. We then made use of multiwaveband archives to search for counterparts at other wavelengths of these XRT detections and exploited X-ray spectral information in an attempt to determine their nature and association with the IBIS object. As a result of our analysis, we identified a single counterpart for 13 sources, although in some cases its nature/class could not be assessed on the basis of the information collected. More specifically, we found that SWIFT J0924.2−3141 and SWIFT J1839.1−5717 are absorbed AGN, while SWIFT J0800.7−4309 and 1SWXRT J230642.8+550817 are cataclysmic variable binary systems. Finally, we found that IGR J14059−6116 is likely associated with the Fermi source 3FGL J1405.4−6119. In the case of XMMSL1 J030715.5−545536, no XRT counterpart was detected. In all the other cases, optical/infrared spectroscopy is necessary to classify properly each X-ray counterpart and confirm their association with the INTEGRAL/IBIS detection.