  We present our mass estimate of the central black hole in the isolated spiral
galaxy NGC 4414. Using natural guide star adaptive optics assisted observations
with the Gemini Near-Infrared Integral Field Spectrometer (NIFS) and the
natural seeing Gemini Multi-Object Spectrographs-North (GMOS), we derived
two-dimensional stellar kinematic maps of NGC 4414 covering the central 1.5
arcsec and 10 arcsec, respectively, at a NIFS spatial resolution of 0.13
arcsec. The kinematic maps reveal a regular rotation pattern and a central
velocity dispersion dip down to around 105 km/s. We constructed dynamical
methods using two different methods: Jeans anisotropic dynamical modeling and
axisymmetric Schwarzschild modeling. Both modeling methods give consistent
results, but we cannot constrain the lower mass limit and only measure an upper
limit for the black hole mass of Mbh= 1.56 x 10^6 Msun(at 3 sigma level) which
is at least 1 sigma below the recent Mbh-sigma_e relations. Further tests with
dark matter, mass-to-light ratio variation and different light models confirm
that our results are not dominated by uncertainties. The derived upper limit
mass is not only below the Mbh-sigma_e relation, but is also five times lower
than the lower limit black hole mass anticipated from the resolution limit of
the sphere of influence. This proves that via high quality integral field data
we are now able to push black hole measurements down to at least five times
less than the resolution limit.
