  We present the results of a photometric and astrometric study of the low mass
stellar and substellar population of the young open cluster Blanco 1. We have
exploited J band data, obtained recently with the Wide Field Camera (WFCAM) on
the United Kingdom InfraRed Telescope (UKIRT), and 10 year old I and z band
optical imaging from CFH12k and Canada France Hawaii Telescope (CFHT), to
identify 44 candidate low mass stellar and substellar members, in an area of 2
sq. degrees, on the basis of their colours and proper motions. This sample
includes five sources which are newly discovered. We also confirm the lowest
mass candidate member of Blanco 1 unearthed so far (29MJup). We determine the
cluster mass function to have a slope of alpha=+0.93, assuming it to have a
power law form. This is high, but nearly consistent with previous studies of
the cluster (to within the errors), and also that of its much better studied
northern hemisphere analogue, the Pleiades.
