Search for K+ decays to a lepton and invisible particles



Lurkin, Nicolas, Akmete, A, Aliberti, R, Ambrosino, F, Ammendola, R, Angelucci, B, Antonelli, A, Anzivino, G, Arcidiacono, R, Bache, T
et al (show 216 more authors) (2022) Search for K+ decays to a lepton and invisible particles. In: The 22nd International Workshop on Neutrinos from Accelerators, 2021-9-6 - ?.

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Abstract

The NA62 experiment at CERN reports searches for K+ → e+N, K+ → µ+N and K+ → µ+X decays, where N and X are massive invisible particles, using the 2016-2018 data set. The N particle is assumed to be a heavy neutral lepton, and the results are expressed as upper limits of O(10−9) and O(10−8) on the neutrino mixing parameter |Ue4|2 and |Uµ4|2, improving on the earlier searches for heavy neutral lepton production and decays in the kinematically accessible mass range. The X particle is considered a scalar or vector hidden sector mediator decaying to an invisible final state, and upper limits of the decay branching fraction for X masses in the range 10-370 MeV/c2 are reported for the first time, ranging from O(10−5) to O(10−7). An upper limit of 1.0 · 10−6 is established at 90% CL on the K+ → µ+ννν¯ branching fraction.

Item Type: Conference or Workshop Item (Unspecified)
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 14 Mar 2023 15:55
Last Modified: 09 Sep 2024 02:37
DOI: 10.22323/1.402.0157
Open Access URL: https://pos.sissa.it/402/157/
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3169067