Search for Strange-Pentaquark Production in e+e− Annihilation at √s=10.58 GeVc

Abstract

We search for strange-pentaquark states that have been previously reported by other experiments the Θ ( 1540 ) + , Ξ 5 ( 1860 ) −− , and Ξ 5 ( 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 Ξ 5 ( 1860 ) −− pentaquarks produced per e + e − annihilation into q ¯ q and per Υ ( 4 S ) decay. For q ¯ q events the Θ ( 1540 ) + [ Ξ 5 ( 1860 ) −− ] limit is about 8 [4] times lower than the rates measured for ordinary baryons of similar mass.