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arXiv · 1002.1076

Revealing the nature of new unidentified INTEGRAL sources

N. Masetti·P. Parisi·E. Palazzi·L. Bassani·R. Landi·A. Malizia·F. Schiavone·J. B. Stephen·E. Jimenez-Bailon·V. Chavushyan·L. Morelli·E. Mason·G. Galaz·D. Minniti·A. J. Bird·A. J. Dean·V. A. McBride·P. A. Charles·A. Bazzano·P. Ubertini
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Abstract

Since its launch on 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. However, the combined use of available information at longer wavelengths (mainly soft X-rays and radio) and of optical spectroscopy on the putative counterparts of these new hard X-ray objects allows pinpointing their exact nature. Continuing our long-standing program running since 2004 (and with which we identified more than 100 INTEGRAL objects) here we report the classification, through optical spectroscopy, of 25 unidentified high-energy sources mostly belonging to the recently published 4th IBIS survey.

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N. Masetti, P. Parisi, E. Palazzi, L. Bassani, R. Landi, A. Malizia, F. Schiavone, J. B. Stephen, E. Jimenez-Bailon, V. Chavushyan, L. Morelli, E. Mason, G. Galaz, D. Minniti, A. J. Bird, A. J. Dean, V. A. McBride, P. A. Charles, A. Bazzano, P. Ubertini. 2010-02-04. Revealing the nature of new unidentified INTEGRAL sources. https://doi.org/10.1142/s0218271810016701

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