@article{05f1345d602f4841a222b6dfaa48064c,
title = "Search for heavy neutral leptons in π+ decays to positrons",
abstract = "A search for heavy neutral lepton (N) production in π+→e+N in-flight decays using data collected by the NA62 experiment at CERN in 2017–2024 is reported. Upper limits for the extended neutrino mixing matrix element |Ue4|2 are established at the level of 10−8 for heavy neutral leptons with mass in the range 95–126 MeV/c2 and lifetime exceeding 50 ns.",
author = "\{The NA62 Collaboration\} and B. Bloch-Devaux and \{Cortina Gil\}, E. and N. Lurkin and E. Minucci and S. Padolski and P. Petrov and T. Numao and Y. Petrov and V. Shang and B. Velghe and Wong, \{V. W.S.\} and D. Bryman and J. Fu and L. Bician and Z. Hives and T. Husek and K. Kampf and M. Kolesar and M. Koval and \{De Martino\}, B. and M. Perrin-Terrin and L. Petit and B. D{\"o}brich and J. Jerhot and S. Lezki and J. Schubert and Akmete, \{A. T.\} and R. Aliberti and M. Ceoletta and \{Di Lella\}, L. and N. Doble and G. Khoriauli and J. Kunze and D. Lomidze and L. Peruzzo and C. Polivka and S. Schuchmann and M. Vormstein and H. Wahl and R. Wanke and L. Bandiera and N. Canale and A. Gianoli and M. Romagnoni and P. Dalpiaz and M. Fiorini and R. Negrello and I. Neri and F. Petrucci and R. Arcidiacono",
note = "Publisher Copyright: {\textcopyright} 2026",
year = "2026",
month = jan,
doi = "10.1016/j.physletb.2025.140119",
language = "English",
volume = "872",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier BV",
}