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Search for the Baryon and Lepton Number Violating Decays tau -> Lambda h

The BABAR Collaboration·B. Aubert
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Abstract

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-) < 5.9 x 10^-8, B(tau- -> Lambda0 pi-) < 5.8 x 10^-8, B(tau- -> anti-Lambda0 K-) < 7.2 x 10^-8, and B(tau- -> Lambda0 K-) < 15 x 10^-8 at 90% confidence level.

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The BABAR Collaboration, B. Aubert. 2006-07-24. Search for the Baryon and Lepton Number Violating Decays tau -> Lambda h. https://arxiv.org/abs/hep-ex/0607040

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