Search for the Lepton-Number-Violating Decay $\hat{I}{ž}^{-}\to p\hat{I}{¼}^{-}\hat{I}{¼}^{-}$

Abstract

A sensitive search for the lepton-number-violating decay $\hat{I}{ž}^{-}\to p\hat{I}{¼}^{-}\hat{I}{¼}^{-}$ has been performed using a sample of $\sim 10^9$ $\hat{I}{ž}^{-}$ hyperons produced in 800 GeV/$c$ $p$-Cu collisions. We obtain $\mathcal{B}(\hat{I}{ž}^{-}\to p\hat{I}{¼}^{-}\hat{I}{¼}^{-})<4.0\times 10^{-8}$ at 90% confidence, improving on the best previous limit by four orders of magnitude.

9 pages, 5 figures, to be published in Phys. Rev. Lett