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Spectropolarimetry of Broad H_alpha Lines and Geometry of the BLR

Marshall H. Cohen·Andre' R. Martel
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Abstract

In a small fraction of Broad Line Radio Galaxies (BLRG) and Seyfert 1 galaxies, the polarization position angle rotates across the broad emission lines, especially at H_alpha. An understanding of this behavior can potentially yield important information on the scattering geometry in the nucleus. We show two examples of this phenomenon, 3C 445, a BLRG, and Mrk 231, a Seyfert 1, and present an equatorial scattering model that explains some of its features in a straightforward way.

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Marshall H. Cohen, Andre' R. Martel. 2001-06-09. Spectropolarimetry of Broad H_alpha Lines and Geometry of the BLR. https://arxiv.org/abs/astro-ph/0106168

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