The obscured X-ray source population in the HELLAS2XMM survey: the Spitzer view

C. Vignali; Francesca Pozzi; A. Comastri; L. Pozzetti; M. Mignoli; C. Gruppioni; G. Zamorani; C. Lari; F. Civano; M. Brusa; F. Fiore; R. Maiolino

doi:10.1063/1.2774954

arXiv · 0704.1300

The obscured X-ray source population in the HELLAS2XMM survey: the Spitzer view

C. Vignali·Francesca Pozzi·A. Comastri·L. Pozzetti·M. Mignoli·C. Gruppioni·G. Zamorani·C. Lari·F. Civano·M. Brusa·F. Fiore·R. Maiolino

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Abstract

Recent X-ray surveys have provided a large number of high-luminosity, obscured Active Galactic Nuclei (AGN), the so-called Type 2 quasars. Despite the large amount of multi-wavelength supporting data, the main parameters related to the black holes harbored in such AGN are still poorly known. Here we present the results obtained for a sample of eight Type 2 quasars in the redshift range 0.9-2.1 selected from the HELLAS2XMM survey, for which we used Ks-band, Spitzer IRAC and MIPS data at 24 micron to estimate bolometric corrections, black hole masses, and Eddington ratios.

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C. Vignali, Francesca Pozzi, A. Comastri, L. Pozzetti, M. Mignoli, C. Gruppioni, G. Zamorani, C. Lari, F. Civano, M. Brusa, F. Fiore, R. Maiolino. 2007-04-10. The obscured X-ray source population in the HELLAS2XMM survey: the Spitzer view. https://doi.org/10.1063/1.2774954

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