Search for the Theta(1540) Pentaquark in Electro-Production with the BaBar Detector

Since early in 2003, several experiments have presented evidence for the existence of a positive strangeness baryon state of mass around 1540 $MeV/c^2$ and width $< 8$ MeV, the Theta(1540), which decays to $K^+ n$ and $K^0 p$. Such a state has minimum quark content u d u d sbar and consequently has been interpreted as the S = +1 member of the anti-decouplet of pentaquark states proposed by Diakonov et al. Six of the claimed observations involve real or virtual photoproduction. We present preliminary results from a search for the production of the Theta(1540) in $e^+ e^-$ interactions (i.e. virtual photoproduction) in the Be beampipe of the BaBar Detector at the PEP-II Collider. Event selection procedures are summarised and $K^0_S$ p invariant mass distributions in the threshold region are presented.