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The Suzaku view of 3C 382

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 نشر من قبل Francesco Tombesi PhD
 تاريخ النشر 2011
  مجال البحث فيزياء
والبحث باللغة English
 تأليف R. M. Sambruna




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We present a long Suzaku observation of 3C 382. A Swift BAT spectrum from the 58-month survey is also analyzed, together with an archival XMM-Newton EPIC exposure. Our main result is the finding with Suzaku of a broad FeK line with a relativistic profile consistent with emission from an accretion disk at tens of gravitational radii from the central black hole. The XIS data indicate emission from highly ionized iron and allow us to set tight, albeit model-dependent, constraints on the inner and outer radii of the disk reflecting region, r_in~10r_g and r_out~20r_g, respectively, and on the disk inclination, i~30deg. Two ionized reflection components are possibly observed, with similar contributions of ~10% to the total continuum. A highly ionized one, with log_xi~3, which successfully models the relativistic line and a mildly ionized one, with log_xi~1.5, which models the narrow Fe K line and high energy hump. When both these components are included, there is no further requirement for an additional black body soft excess below 2keV. The Suzaku data confirm the presence of a warm absorber previously known from grating studies. After accounting for all the spectral features, the intrinsic photon index of the X-ray continuum is ~1.8 with a cutoff energy at ~200keV, consistent with Comptonization models and excluding jet-related emission up to these energies. Comparison of the X-ray properties of 3C 382 and other BLRGs to Seyferts confirms the idea that the distinction between radio-loud and radio-quiet AGN at X-rays is blurred.



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