A search for the $K^{+}\to {\mu }^{-}\nu e^{+}{e}^{+}$ decay

Abstract

A search for the $K^{+}\to {\mu }^{-}\nu e^{+}{e}^{+}$ decay, forbidden within the Standard Model by either lepton number or lepton flavour conservation depending on the flavour of the emitted neutrino, has been performed using the dataset collected by the NA62 experiment at CERN in 2016--2018. An upper limit of $8.1\times 10^{-11}$ is obtained for the decay branching fraction at 90% CL, improving by a factor of 250 over the previous search.

Final version, published in Physics Letters B

References in corpus (2)

• The integrated low-level trigger and readout system of the CERN NA62 experiment
• Searches for lepton number violating $K^{+}\to {\pi }^{-}({\pi }^0)e^{+}{e}^{+}$ decays

Cited by in corpus (1)

• Workshop summary -- Kaons@CERN 2023