Abstract
Water megamasers have been found to trace parsec/sub-parsec, circumnuclear accretion disks in several AGN (e.g., Circinus, NGC 1068 & NGC 4258). High-spatial (0.5 mas) and velocity resolution (0.2 km s−1) VLBA imaging of the disks reveals thin, warped ‘pannekoeken (pancake)’-style structures as opposed to thick tori in the inner regions of the central engines (40 000 Rsch). In this contribution, I will describe some current investigations into the dynamical and physical attributes of the water maser disk in NGC 4258, as revealed by VLBA, VLA and Effelsberg monitoring over 8 years.
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Humphreys, E., Argon, A., Greenhill, L., Reid, M., Moran, J. (2005). The Sub-PC Scale Accretion Disk of NGC 4258. In: Baan, W., Hagiwara, Y., van Langevelde, H. (eds) Dense Molecular Gas Around Protostars and in Galactic Nuclei. Springer, Dordrecht. https://doi.org/10.1007/1-4020-3831-3_33
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DOI: https://doi.org/10.1007/1-4020-3831-3_33
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