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arXiv · 1006.4462

Five new INTEGRAL unidentified hard X-Ray sources uncovered by Chandra

M. Fiocchi·L. Bassani·A. Bazzano·P. Ubertini·R. Landi·F. Capitanio·A. J. Bird
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Abstract

The IBIS imager on board INTEGRAL, with a sensitivity better than a mCrab in deep observations and a point source location accuracy of the order of few arcminutes, has localized so far 723 hard X-ray sources in the 17--100 keV energy band, of which a fraction of about 1/3 are still unclassified. The aim of this research is to provide sub-arcsecond localizations of the unidentified sources, necessary to pinpoint the optical and/or infrared counterpart of those objects whose nature is so far unknown. The cross-correlation between the new IBIS sources published within the fourth INTEGRAL/IBIS Survey catalogue and the CHANDRA/ACIS data archive resulted in a sample of 5 not yet identified objects. We present here the results of CHANDRA X-ray Observatory observations of these five hard X-ray sources discovered by the INTEGRAL satellite. We associated IGR J10447-6027 with IR source 2MASSJ10445192-6025115, IGR J16377-6423 with the cluster CIZA J1638.2-6420, IGR J14193-6048 with the pulsar with nebula PSR J1420-6048 and IGR J12562+2554 with the Quasar SDSSJ125610.42+260103.5. We suggest that the counterpart of IGR J12288+0052 may be an AGN/QSO type~2 at a confidence level of 90%.

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M. Fiocchi, L. Bassani, A. Bazzano, P. Ubertini, R. Landi, F. Capitanio, A. J. Bird. 2010-06-23. Five new INTEGRAL unidentified hard X-Ray sources uncovered by Chandra. https://doi.org/10.1088/0004-637x%2F720%2F2%2F987

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