  A recent study demonstrated that there is significant covariance structure in
the noise on data from ground-based photometric surveys designed to detect
transiting extrasolar planets. Such correlation in the noise has often been
overlooked, especially when predicting the number of planets a particular
survey is likely to find. Indeed, the shortfall in the number of transiting
extrasolar planets discovered by such surveys seems to be explained by
co-variance in the noise. We analyse SuperWASP (Wide Angle Search for Planets)
data and determine that there is a significant amount of correlated systematic
noise present. After modelling the potential planet catch, we conclude that
this noise places a significant limit on the number of planets that SuperWASP
is likely to detect; and that the best way to boost the signal-to-noise ratio
and limit the impact of co-variant noise is to increase the number of observed
transits for each candidate transiting planet.
