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A Survey for H2O Megamasers III. Monitoring Water Vapor Masers in Active Galaxies

J. A. Braatz·A. S. Wilson·C. Henkel·R. Gough·M. Sinclair
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Abstract

We present single-dish monitoring of the spectra of 13 extragalactic water megamasers taken over a period of 9 years and a single epoch of sensitive spectra for 7 others. Our data include the first K-band science observations taken with the new 100 m Green Bank Telescope (GBT). In the context of a circumnuclear, molecular disk model, our results suggest that either (a) the maser lines seen are systemic features subject to a much smaller acceleration than present in NGC 4258, presumably because the gas is farther from the nuclear black hole, or (b) we are detecting ``satellite'' lines for which the acceleration is in the plane of the sky. We also report a search for water vapor masers towards the nuclei of 58 highly inclined, nearby galaxies.

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J. A. Braatz, A. S. Wilson, C. Henkel, R. Gough, M. Sinclair. 2003-02-12. A Survey for H2O Megamasers III. Monitoring Water Vapor Masers in Active Galaxies. https://doi.org/10.1086/374417

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