Search for the Baryon and Lepton Number Violating Decays tau -> Lambda h
The BABAR Collaboration, B Aubert · arXiv (Cornell University) · 2006
We have searched for the violation of baryon number B and lepton number L in the (B-L)-conserving modes tau- -> anti-Lambda0 pi- and tau- -> anti-Lambda0 K- as well as the (B-L)-violating modes tau- -> Lambda0 pi- and tau- -> Lambda0 K- using 237 inv. fb of data collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. We do not observe any signal and determine preliminary upper limits on the branching fractions B(tau- -> anti-Lambda0 pi-) Lambda0 pi-) anti-Lambda0 K-) Lambda0 K-) < 15 x 10^-8 at 90% confidence level.