Search for K+ decays to a muon and invisible particles
(2021) In Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 816.- Abstract
The NA62 experiment at CERN reports searches for K+→μ+N and K+→μ+νX 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(10−8) of the neutrino mixing parameter |Uμ4|2 for N masses in the range 200–384 MeV/c2 and lifetime exceeding 50 ns. 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... (More)
The NA62 experiment at CERN reports searches for K+→μ+N and K+→μ+νX 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(10−8) of the neutrino mixing parameter |Uμ4|2 for N masses in the range 200–384 MeV/c2 and lifetime exceeding 50 ns. 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 improved upper limit of 1.0×10−6 is established at 90% CL on the K+→μ+ννν¯ branching fraction.
(Less)
- author
- Cortina Gil, E. and Husek, T. LU
- author collaboration
- organization
- publishing date
- 2021-05-10
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
- volume
- 816
- article number
- 136259
- publisher
- Elsevier
- external identifiers
-
- scopus:85104114266
- ISSN
- 0370-2693
- DOI
- 10.1016/j.physletb.2021.136259
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2021 The Author(s)
- id
- 3fc5dbea-638c-45f8-9858-c957af3f0137
- date added to LUP
- 2022-03-30 11:39:40
- date last changed
- 2025-04-04 14:54:51
@article{3fc5dbea-638c-45f8-9858-c957af3f0137, abstract = {{<p>The NA62 experiment at CERN reports searches for K<sup>+</sup>→μ<sup>+</sup>N and K<sup>+</sup>→μ<sup>+</sup>νX 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<sup>−8</sup>) of the neutrino mixing parameter |U<sub>μ4</sub>|<sup>2</sup> for N masses in the range 200–384 MeV/c<sup>2</sup> and lifetime exceeding 50 ns. 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/c<sup>2</sup> are reported for the first time, ranging from O(10<sup>−5</sup>) to O(10<sup>−7</sup>). An improved upper limit of 1.0×10<sup>−6</sup> is established at 90% CL on the K<sup>+</sup>→μ<sup>+</sup>ννν¯ branching fraction.</p>}}, author = {{Cortina Gil, E. and Husek, T.}}, issn = {{0370-2693}}, language = {{eng}}, month = {{05}}, publisher = {{Elsevier}}, series = {{Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics}}, title = {{Search for K<sup>+</sup> decays to a muon and invisible particles}}, url = {{http://dx.doi.org/10.1016/j.physletb.2021.136259}}, doi = {{10.1016/j.physletb.2021.136259}}, volume = {{816}}, year = {{2021}}, }