A search for the lepton number violating K+ ? p-µ+e+ and lepton flavour violating K+ ? p-µ-e+ decays is reported using NA62 data collected in 2017 and 2018. No significant excess is observed above the background expectation and therefore upper limits are established on the branching ratios at 90% confidence level: B(K+ ? p-µ+e+) < 4.2 × 10-11 and B(K+ ? p+µ-e+) < 6.6 × 10-11. These results improve over the previous limits by factors of 12 and 8 respectively.
|Title of host publication||Proceedings of Science|
|Publication status||Published - 15 Apr 2021|
|Event||40th International Conference on High Energy Physics, ICHEP 2020 - Virtual, Prague, Czech Republic|
Duration: 28 Jul 2020 → 6 Aug 2020
|Name||Proceedings of Science|
|Conference||40th International Conference on High Energy Physics, ICHEP 2020|
|Period||28/07/20 → 6/08/20|
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