Evidence for B{sup +} {yields} J/{psi} p{bar {Lambda}} and search for B{sup 0} {yields} J/{psi} p{bar p}

Abstract

We have performed a search for the decays B{sup +} {yields} J/{psi}p{bar {Lambda}} and B{sup 0} {yields} J/{psi}p{bar p} in a data set of (88.9 {+-} 1.0) x 10{sup 6} {Upsilon}(4S) decays collected by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring at the Stanford Linear Accelerator Center. Four charged B candidates have been observed with an expected background of 0.21 {+-} 0.14 events. The corresponding branching fraction is (12{sub -6}{sup +9} x 10{sup -6}), where statistical and systematic uncertainties have been combined. The result can be interpreted as a 90% confidence level (CL) upper limit of 26 x 10{sup -6}. We also find one B{sup 0} candidate, with an expected background of 0.64 {+-} 0.17 events, implying a 90% CL upper limit of 1.9 x 10{sup -6}.