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Accretion and Outflow Traced by Water Masers in the Circinus AGN

L. J. Greenhill·J. M. Moran·R. S. Booth·S. P. Ellingsen·P. M. McCulloch·D. L. Jauncey·R. P. Norris·J. E. Reynolds·A. K. Tzioumis·J. R. Herrnstein
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Abstract

The first VLBI images of water maser emission in the Circinus Galaxy AGN show both a warped, edge-on accretion disk and an outflow 0.1 to 1 pc from the central engine. The inferred central mass is 1.3 million suns, while the disk mass may be on the order of 0.1 million suns, based on a nearly Keplerian rotation curve. The bipolar, wide-angle outflow appears to contain ``bullets'' ejected from within <0.1 pc of the central mass. The positions of filaments and bullets observed in the AGN ionization cone on kpc-scales suggest that the disk channels the flow to a radius of about 0.4 pc, at which the flow appears to disrupt the disk.

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L. J. Greenhill, J. M. Moran, R. S. Booth, S. P. Ellingsen, P. M. McCulloch, D. L. Jauncey, R. P. Norris, J. E. Reynolds, A. K. Tzioumis, J. R. Herrnstein. 2000-12-01. Accretion and Outflow Traced by Water Masers in the Circinus AGN. https://arxiv.org/abs/astro-ph/0012032

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