The Megamaser Cosmology Project. XII. VLBI Imaging of H$_{2}$O Maser
  Emission in Three Active Galaxies and the Effect of AGN Winds on Disk
  Dynamics
  We present VLBI images and kinematics of water maser emission in three active
galaxies: NGC 5728, Mrk 1, and IRAS 08452-0011. IRAS 08452-0011 is a
triple-peaked H2O megamaser, consistent with a Keplerian rotating disk,
indicating a black hole mass of (3.3+/-0.2)x10^7 M_sun. NGC 5728 and Mrk 1
display double-peaked spectra and VLBI imaging reveal complicated gas
kinematics, which do not allow for a robust determination of black hole mass.
The two systems are either gas disks perturbed by AGN winds or part of
outflows. We find that disturbed morphology and kinematics are a ubiquitous
feature of all double-peaked maser systems, implying that these maser sources
may reside in environments where AGN winds are prominent at ~1 pc scale and
have significant impact on the masing gas. Such AGN tend to have black hole
mass M_BH < 8x10^6 M_sun and Eddington ratios lambda_Edd >~ 0.1, while the
triple-peaked megamasers show an opposite trend.
