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X-ray spectroscopy of the broad line radio galaxy 3C111

C. S. Reynolds·K. Iwasawa·C. S. Crawford·A. C. Fabian
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Abstract

We present an ASCA observation of the broad line radio galaxy 3C111. The X-ray spectrum is well described by a model consisting of a photoelectrically-absorbed power-law form. The inferred absorbing column density is significantly greater than expected on the basis of 21-cm measurements of Galactic HI. Whilst this may be due intrinsic absorption from a circumnuclear torus or highly warped accretion disk, inhomogeneities and molecular gas within the foreground giant molecular cloud may also be responsible for some of this excess absorption. We also claim a marginal detection of a broad iron Ka line which is well explained as being a fluorescent line originating from the central regions of a radiatively-efficient accretion disk. This line appears weak in comparison to those found in (radio-quiet) Seyfert nuclei. We briefly discuss the implications of this fact.

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C. S. Reynolds, K. Iwasawa, C. S. Crawford, A. C. Fabian. 1998-05-15. X-ray spectroscopy of the broad line radio galaxy 3C111. https://doi.org/10.1046/j.1365-8711.1998.01791.x

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