  We conducted a search for occultations of bright stars by Kuiper Belt Objects
(KBOs) to estimate the density of sub-km KBOs in the sky. We report here the
first results of this occultation survey of the outer solar system conducted in
June 2007 and June/July 2008 at the MMT Observatory using Megacam, the large
MMT optical imager. We used Megacam in a novel shutterless continuous--readout
mode to achieve high precision photometry at 200 Hz. We present an analysis of
220 star hours at signal-to-noise ratio of 25 or greater. The survey efficiency
is greater than 10% for occultations by KBOs of diameter d>=0.7 km, and we
report no detections in our dataset. We set a new 95% confidence level upper
limit for the surface density \Sigma_N(d) of KBOs larger than 1 km:
\Sigma_N(d>=1 km) <= 2.0e8 deg^-2, and for KBOs larger than 0.7 km \Sigma_N(d>=
0.7 km) <= 4.8e8 deg^-2.
