  Presented are the results of a large and deep optical-near-infrared
multi-epoch survey of the Praesepe open star cluster using data from the UKIDSS
Galactic Clusters Survey. Multiple colour magnitude diagrams were used to
select potential members and proper motions were used to assign levels of
membership probability. From our sample, 145 objects were designated as high
probability members (p >= 0.6) with most of these having been found by previous
surveys although 14 new cluster members are also identified. Our membership
assignment is restricted to the bright sample of objects (Z < 18). From the
fainter sample, 39 candidates were found from an examination of multiple colour
magnitude plots. Of these, 2 have small but significant membership
probabilities. Finally, using theoretical models, cluster luminosity and mass
functions were plotted with the later being fitted with a power law of alpha =
1.11 +/- 0.37 for the mass range 0.6 to 0.125 Msun and an assumed cluster age
of 500 Myrs in the UKIDSS Z photometric band. Likewise taking an assumed
cluster age of 1 Gyr we find alpha = 1.10 +/- 0.37. Similar values were also
found for the J and K bands. These results compare favourably with the result
of Kraus & Hillenbrand (2007) (alpha = 1.4 +/- 0.2) but are significantly lower
than that of the more recent study conducted by Boudreault et al. (2009) (alpha
= 1.8 +/- 0.1).
