Search for the Lepton-Number-Violating Decay $Ξ^- \to p μ^- μ^-$

HyperCP Collaboration; Rajaram, D.; Burnstein, R. A.; Chakravorty, A.; Chen, Y. C.; Choong, W. -S.; Clark, K.; Dukes, E. C.; Durandet, C.; Felix, J.; Fu, Y.; Gidal, G.; Gustafson, H. R.; Holmstrom, T.; Huang, M.; James, C.; Jenkins, C. M.; Jones, T. D.; Kaplan, D. M.; Longo, M. J.; Lu, L. C.; Luebke, W.; Luk, K. -B.; Nelson, K. S.; Park, H. K.; Perroud, J. -P.; Rubin, H. A.; Volk, J.; White, C. G.; White, S. L.; Zyla, P.

Search for the Lepton-Number-Violating Decay $Ξ^- \to p μ^- μ^-$

Authors

HyperCP Collaboration

Description

A sensitive search for the lepton-number-violating decay $Ξ^-\to p μ^-μ^-$ has been performed using a sample of $\sim10^9$ $Ξ^-$ hyperons produced in 800 GeV/$c$ $p$-Cu collisions. We obtain $\mathcal{B}(Ξ^-\to p μ^-μ^-)< 4.0\times 10^{-8}$ 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