Proc. IAU volume 13, issue S336, P125-128 2017 DOI: 10.1017/s1743921317009966 View full text
Dominic Pesce, James Braatz, James Condon, Feng Gao, Christian Henkel, Violette Impellizzeri, Eugenia Litzinger, K. Y. Lo, Mark Reid

Abstract: AbstractMany accretion disks surrounding supermassive black holes in nearby AGN are observed to host 22 GHz water maser activity. We have analyzed single-dish 22 GHz spectra taken with the GBT to identify 32 such “Keplerian disk systems,” which we used to investigate maser excitation and explore the possibility of disk reverberation. Our results do not support a spiral shock model for population inversion in these disks, and we find that any reverberating signal propagating radially outwards from the AGN must …

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