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For refcode 1998ApJ...493...91T:
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1998ApJ...493...91T ASCA Observations of Type 2 Seyfert Galaxies. III. Orientation and X-Ray Absorption T. J. TURNER, I. M. GEORGE, K. NANDRA, AND R. F. MUSHOTZKY Received 1997 April 29; accepted 1997 September 2 ABSTRACT We discuss the spectral properties of a sample of type 2 Seyfert galaxies based upon the analysis of ASCA data. In this paper, we consider the sources for which the X-ray spectra appear to be dominated by the nuclear continuum, transmitted through a large column of absorbing material. We find that both Seyfert 2 galaxies and narrow emission line galaxies (NELGs) show iron K{alpha} line profiles indicative of reprocessing of nuclear X-rays in a face-on accretion disk. Such line profiles are also observed in Seyfert 1 galaxies. This result is contrary to unification models, which would predict the inner regions of transmitted Seyfert 2 galaxies to be observed edge-on. This raises some questions as to the orientation of the circumnuclear absorber. If the observed differences between Seyfert 1 and 2 galaxies and NELGs are not due to differences in the orientation of the absorbing material, then we suggest that differences in dust composition and grain size, and in the density of the circumnuclear gas, could be of primary importance. Subject headings: galaxies: active-galaxies: nuclei-galaxies: Seyfert-X- rays: galaxies
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