Optical identification of sources from the HELLAS2XMM survey

F. Fiore; G. Matt; F. La Franca; G. C. Perola; M. Brusa; A. Comastri; M. Mignoli; P. Ciliegi; P. Severgnini; R. Maiolino; A. Baldi; S. Molendi; C. Vignali

arXiv · astro-ph/0109116

Optical identification of sources from the HELLAS2XMM survey

F. Fiore·G. Matt·F. La Franca·G. C. Perola·M. Brusa·A. Comastri·M. Mignoli·P. Ciliegi·P. Severgnini·R. Maiolino·A. Baldi·S. Molendi·C. Vignali

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Abstract

We present preliminary results on the optical identifications of sources from the High Energy Large Area Survey performed with XMM-Newton (HELLAS2XMM). This survey covers about 3 square degrees of sky down to a 2-10 keV flux of 7 x 10^-15 erg cm-2 s-1 (Baldi & Molendi these proceedings, Baldi et al. 2001). The survey good sensitivity over a large area allows us to confirm and extend previous Chandra results about a population of X-ray luminous but optically dull galaxies emerging at 2-10 keV fluxes of about 10-14 erg cm-2 s-1. Although the statistics are still rather poor, it appears that at these X-ray fluxes the fraction of these galaxies is similar or even higher than that of narrow line AGN.

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F. Fiore, G. Matt, F. La Franca, G. C. Perola, M. Brusa, A. Comastri, M. Mignoli, P. Ciliegi, P. Severgnini, R. Maiolino, A. Baldi, S. Molendi, C. Vignali. 2001-09-07. Optical identification of sources from the HELLAS2XMM survey. https://arxiv.org/abs/astro-ph/0109116

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