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AGN Disk Diagnostics

Blandford, R. D. (1998) AGN Disk Diagnostics. Highlights of Astronomy, 11 (2). pp. 964-967. ISSN 1539-2996. doi:10.1017/S1539299600019304.

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The discovery of megamasers in nearby active galactic nuclei (AGN) is an unexpected boon for AGN researchers. The most immediate benefit, brought out in observations of NGC4258 (Miyoshi et al 1995, Moran, these proceedings) is that it allows an accurate mass measurement for the central black hole, in this case of 3.6 x 107 M⊙, with unprecedented accuracy. (I shall not belabor the point that we have not proven rigorously that it is a black hole because this is surely on much firmer footing than what follows!) Masers also allow us to discover second order features of the kinematics, specifically that the disk is warped. Thirdly, and this is what I have been asked to review here, it should enable us to choose between several possible accretion modes by treating masers as diagnostic probes of physical conditions in the disk.

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Blandford, R. D.0000-0002-1854-5506
Additional Information:© 1998 IAU. I thank Willem Baan for the opportunity to learn more about AGN maser disks and James Herrnstein, Jim Moran, Ramesh Narayan, Rob Nelson and Sterl Phinney for helpful conversations. Support under NSF grant AST 95-29170 is gratefully acknowledged.
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NSFAST 95-29170
Issue or Number:2
Record Number:CaltechAUTHORS:20181119-160810928
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Official Citation:Blandford, R. (1998). AGN Disk Diagnostics. Highlights of Astronomy, 11(2), 964-967. doi:10.1017/S1539299600019304
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91042
Deposited By: Tony Diaz
Deposited On:20 Nov 2018 00:16
Last Modified:16 Nov 2021 03:37

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