Search for Lepton Number and Flavor Violation in K^{+} and π^{0} Decays

The NA62 Collaboration

Research output: Contribution to journalArticle (Academic Journal)peer-review

24 Citations (Scopus)
32 Downloads (Pure)


Searches for the lepton number violating decay and the lepton flavor violating and decays are reported using data collected by the NA62 experiment at CERN in 2017-2018. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level: , and . These results improve by 1 order of magnitude over previous results for these decay modes.

Original languageEnglish
Article number131802
JournalPhysical Review Letters
Issue number13
Publication statusPublished - 24 Sept 2021

Bibliographical note

Funding Information:
The cost of the experiment and its auxiliary systems was supported by the funding agencies of the Collaboration Institutes. We are particularly indebted to F. R. S.-FNRS (Fonds de la Recherche Scientifique—FNRS), Belgium; NSERC (Natural Sciences and Engineering Research Council), funding SAPPJ-2018-0017 Canada; MEYS (Ministry of Education, Youth and Sports), Czech Republic; BMBF (Bundesministerium für Bildung und Forschung) Contracts No. 05H12UM5, No. 05H15UMCNA, and No. 05H18UMCNA, Germany; INFN (Istituto Nazionale di Fisica Nucleare), Italy; MIUR (Ministero dell’Istruzione, dell’Università e della Ricerca), Italy; CONACyT (Consejo Nacional de Ciencia y Tecnología), Mexico; IFA (Institute of Atomic Physics) Romanian CERN-RO No. 1/16.03.2016 and Nucleus Programme PN 19 06 01 04, Romania; INR-RAS (Institute for Nuclear Research of the Russian Academy of Sciences), Moscow, Russia; JINR (Joint Institute for Nuclear Research), Dubna, Russia; NRC (National Research Center) “Kurchatov Institute” and MESRF (Ministry of Education and Science of the Russian Federation), Russia; MESRS (Ministry of Education, Science, Research and Sport), Slovakia; CERN (European Organization for Nuclear Research), Switzerland; STFC (Science and Technology Facilities Council), United Kingdom; NSF (National Science Foundation) Grants No. 1506088 and No. 1806430, U.S.A.; ERC (European Research Council) “UniversaLepto” advanced grant 268062, “KaonLepton” starting grant 336581, Europe. Individuals have received support from Charles University Research Center (UNCE/SCI/013), Czech Republic; Ministero dell’Istruzione, dell’Universita e della Ricerca (MIUR “Futuro in ricerca 2012” Grant No. RBFR12JF2Z, Project GAP), Italy; Russian Science Foundation (RSF 19-72-10096), Russia; the Royal Society (Grants No. UF100308, No. UF0758946), United Kingdom; STFC (Rutherford fellowships ST/J00412X/1, ST/M005798/1), United Kingdom; ERC (Grants No. 268062, No. 336581 and starting Grant No. 802836 “AxScale”); EU Horizon 2020 (Marie Skłodowska-Curie Grants No. 701386, No. 754496, No. 842407, No. 893101).

Funding Information:
Fonds De La Recherche Scientifique - FNRS Natural Sciences and Engineering Research Council of Canada Ministerstvo ?kolstv?, Ml?de?e a T?lov?chovy Bundesministerium f?r Bildung und Forschung Instituto Nazionale di Fisica Nucleare Ministero dell?Istruzione, dell?Universit? e della Ricerca Consejo Nacional de Ciencia y Tecnolog?a Institutul de Fizic? Atomic? Russian Academy of Sciences Joint Institute for Nuclear Research National Research Center "Kurchatov Institute" Ministry of Education and Science of the Russian Federation Ministerstvo ?kolstva, vedy, v?skumu a ?portu Slovenskej republiky CERN Science and Technology Facilities Council National Science Foundation European Research Council Univerzita Karlova v Praze Russian Science Foundation Royal Society H2020 Marie Sk?odowska-Curie Actions

Publisher Copyright:
© 2021 Published by the American Physical Society


Dive into the research topics of 'Search for Lepton Number and Flavor Violation in K^{+} and π^{0} Decays'. Together they form a unique fingerprint.

Cite this