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Investigation of the obscuring circumnuclear torus in the active galaxy Mrk231

Hans-Rainer Kl"ockner·Willem A. Baan·Michael A. Garrett
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Abstract

Here we report on observations of powerful hydroxyl (OH) line emissions that trace the obscuring material within the circumnuclear environment of the galaxy Markarian 231. The hydroxyl (mega)-maser emission shows the characteristics of a rotating, dusty, molecular torus (or thick disk) located between 30 and 100 pc from the central engine. We now have a clear view of the physical conditions, the kinematics and the spatial structure of this material on intermediate size scales, confirming the main tenets of unification models.

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Hans-Rainer Kl"ockner, Willem A. Baan, Michael A. Garrett. 2003-02-19. Investigation of the obscuring circumnuclear torus in the active galaxy Mrk231. https://arxiv.org/abs/astro-ph/0302395

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