Search for lepton number and flavour violation in $K^{+}$ and ${\pi }^0$ decays

NA62 Collaboration

Searches for the lepton number violating $K^{+}\to {\pi }^{-}{\mu }^{+}{e}^{+}$ decay and the lepton flavour violating $K^{+}\to {\pi }^{+}{\mu }^{-}{e}^{+}$ and $π^{0} \rightarrow μ…