The Structure of the Broad Line Region in AGN: I. Reconstructed
  Velocity-Delay Maps
  We present velocity-resolved reverberation results for five active galactic
nuclei. We recovered velocity-delay maps using the maximum-entropy method for
four objects: Mrk 335, Mrk 1501, 3C120, and PG2130+099. For the fifth, Mrk 6,
we were only able to measure mean time delays in different velocity bins of the
Hbeta emission line. The four velocity-delay maps show unique dynamical
signatures for each object. For 3C120, the Balmer lines show kinematic
signatures consistent with both an inclined disk and infalling gas, but the
HeII 4686 emission line is suggestive only of inflow. The Balmer lines in Mrk
335, Mrk 1501, and PG 2130+099 show signs of infalling gas, but the HeII
emission in Mrk 335 is consistent with an inclined disk. We also see tentative
evidence of combined virial motion and infalling gas from the velocity-binned
analysis of Mrk 6. The maps for 3C120 and Mrk 335 are two of the most clearly
defined velocity-delay maps to date. These maps constitute a large increase in
the number of objects for which we have resolved velocity-delay maps and
provide evidence supporting the reliability of reverberation-based black hole
mass measurements.
