Search for Strange-Pentaquark Production in e+e- Annihilation at s=10.58 GeV

We search for strange-pentaquark states that have been previously reported by other experiments—the Θ(1540)+, Ξ5(1860)--, and Ξ5(1860)0—in 123  fb-1 of data recorded with the BABAR detector at the PEP-II e+e- storage ring. We find no evidence for these states and set 95% confidence level upper limits on the number of Θ(1540)+ and Ξ5(1860)-- pentaquarks produced per e+e- annihilation into qq̅ and per Υ(4S) decay. For qq̅ events the Θ(1540)+ [Ξ5(1860)--] limit is about 8 [4] times lower than the rates measured for ordinary baryons of similar mass.