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Electron-muon conversion in nuclei and rare decays induced by a lepton-flavor-violating dark photon

Alexey S. Zhevlakov1,2,*, Sergey Kuleshov3,4,†, Valery E. Lyubovitskij5,3,‡, and Evgenie O. Oleynik1

  • *Contact author: zhevlakov@theor.jinr.ru
  • †Contact author: sergey.kuleshov@unab.cl
  • ‡Contact author: valeri.lyubovitskij@uni-tuebingen.de
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Phys. Rev. D 113, 015036 – Published 23 January, 2026

DOI: https://doi.org/10.1103/h3qf-m7mb

Abstract

We study lepton-flavor-violation (LFV) effects occurring in the e−μ conversion in nuclei and in the rare radiative decays η(η′)→γμe of the η and η′ mesons with a special impact of the sub-GeV mass vector mediator (dark photon). In the case of the lepton conversion, we make estimates for running and future experiments operating with electron beams at fixed target. Obtained results are implemented in analysis of the LFV decays η(η′)→γμe.

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Phys. Rev. D 113, 015036– Published 23 January, 2026
  • Received 29 July 2025
  • Accepted 23 December 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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