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  • Compton-thick AGNs in the N...
    Marchesi, S.; Ajello, M.; Marcotulli, L.; Comastri, A.; Lanzuisi, G.; Vignali, C.

    The Astrophysical journal, 02/2018, Letnik: 854, Številka: 1
    Journal Article

    We present the 2-100 keV spectral analysis of 30 candidate Compton-thick-(CT-)active galactic nuclei (AGNs) selected in the Swift-Burst Alert Telescope (BAT) 100 month survey. The average redshift of these objects is , and they all lie within ∼500 Mpc. We used the MyTorus model to perform X-ray spectral fittings both without and with the contribution of the Nuclear Spectroscopic Telescope Array (NuSTAR) data in the 3-50 keV energy range. When the NuSTAR data are added to the fit, 13 out of 30 of these objects (43% of the whole sample) have intrinsic absorption NH < 1024 cm−2 at the >3 confidence level, i.e., they are reclassified from Compton thick to Compton thin. Consequently, we infer an overall observed fraction of the CT-AGN, with respect to the whole AGN population, lower than the one reported in previous works, as low as ∼4%. We find evidence that this overestimation of NH is likely due to the low quality of a subsample of spectra, either in the 2-10 keV band or in the Swift-BAT one.