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On the Nature of Intrinsic Absorption in Reddened Seyfert 1 Galaxies

D. M. Crenshaw·S. B. Kraemer
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Abstract

We discuss the origin of the ``dusty lukewarm absorber'', which we previously identified in the reddened Seyfert 1 galaxies NGC 3227 and Akn 564. This absorber is characterized by saturated UV absorption lines (C IV, N V) near the systemic velocity of the host galaxy, and is likely responsible for reddening both the continuum and the emission lines (including those from the narrow-line region) from these Seyferts. From a large sample of Seyfert 1 galaxies, we find that continuum reddening (as measured by UV color) tends to increase with inclination of the host galaxy. Furthermore, reddened, inclined Seyfert galaxies observed at moderate to high spectral resolution all show evidence for dusty lukewarm absorbers. We suggest that these absorbers lie in the plane of the host galaxy at distances > 100 pc from the nucleus, and are physically distinct from the majority of intrinsic absorbers that are outflowing from the nucleus.

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D. M. Crenshaw, S. B. Kraemer. 2001-10-12. On the Nature of Intrinsic Absorption in Reddened Seyfert 1 Galaxies. https://doi.org/10.1086/337969

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