Search for <overline>Λ-Λ Baryon-Number-Violating Oscillations in the Decay J/ψ → pK - Λ plus c.c.

Ablikim, M.; Achasov, M. N.; Adlarson, P.; Ahmed, S.; Albrecht, M.; Aliberti, R.; Amoroso, A.; An, Q.; Bai, Y.; Bakina, O.; Ferroli, R. Baldini; Balossino, I.; Ban, Y.; Begzsuren, K.; Berger, N.; Bertani, M.; Bettoni, D.; Bianchi, F.; Bloms, J.; Bortone, A.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Calcaterra, A.; Cao, G. F.; Cao, N.; Cetin, S. A.; Chang, J. F.; Chang, W. L.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, M. L.; Chen, S. J.; Chen, X. R.; Chen, Y. B.; Chen, Z. J.; Cheng, W. S.

Science Citation Index Expanded

摘要

We report on the first search for Lambda -Lambda oscillations in the decay J=psi -> pK- Lambda & thorn; c:c: by analyzing 1.31 x 10(9) J=psi events accumulated with the BESIII detector at the BEPCII collider. The J=psi events are produced using e(+) e(-) collisions at a center of mass energy root s= 3.097 GeV. No evidence for hyperon oscillations is observed. The upper limit for the oscillation rate of Lambda to Lambda hyperons is determined to be P(Lambda)=[B(J/psi -> pK(-)Lambda + c:c.)/B(J/psi -> pK(- )Lambda & thorn; c:c.)] < 4.4 x 10(-6) corresponding to an oscillation parameter delta m(Lambda Lambda ) of less than 3.8 x 10(-18 )GeV at the 90% confidence level.

关键词

LEPTON-NUMBER