BeppoSAX uncovers the hidden Seyfert 1 nucleus in the Seyfert 2 galaxy NGC 2110

G. Malaguti; L. Bassani; M. Cappi; A. Comastri; G. DiCocco; A. C. Fabian; G. G. C. Palumbo; T. Maccacaro; R. Maiolino; P. Blanco; M. Dadina; D. DalFiume; F. Frontera; M. Trifoglio

arXiv · astro-ph/9901142

BeppoSAX uncovers the hidden Seyfert 1 nucleus in the Seyfert 2 galaxy NGC 2110

G. Malaguti·L. Bassani·M. Cappi·A. Comastri·G. DiCocco·A. C. Fabian·G. G. C. Palumbo·T. Maccacaro·R. Maiolino·P. Blanco·M. Dadina·D. DalFiume·F. Frontera·M. Trifoglio

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Abstract

The Seyfert 2 galaxy NGC 2110 has been observed with BeppoSAX between 0.5 and 150 keV. The high energy instrument onboard, PDS, has succeeded in measuring for the first time the spectrum of this source in the 13-150 keV range. The PDS spectrum, having a photon index Gamma~1.86 is fully compatible with that expected from a Seyfert 1 nucleus. In the framework of unified models, the harder (Gamma~1.67) 2-10 keV spectrum is well explained assuming the presence of a complex partial + total absorber (Nh~30x10^22 cm^-2 x25% + Nh~4x10^22 cm^-2 x100%). The high column density of this complex absorber is consistent both with the FeK_alpha line strength and with the detection of an absorption edge at E~7.1 keV in the power-law spectrum.

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G. Malaguti, L. Bassani, M. Cappi, A. Comastri, G. DiCocco, A. C. Fabian, G. G. C. Palumbo, T. Maccacaro, R. Maiolino, P. Blanco, M. Dadina, D. DalFiume, F. Frontera, M. Trifoglio. 1999-01-12. BeppoSAX uncovers the hidden Seyfert 1 nucleus in the Seyfert 2 galaxy NGC 2110. https://arxiv.org/abs/astro-ph/9901142

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