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

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 نشر من قبل Cristian Vignali
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف C. Vignali




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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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