2021/10/31 by Julian Heeck, Robert Szafron, Yuichi Uesaka
Physics and Astronomy · #Atomic physics #Electron #Energy (signal processing) #Isotope #Lepton #Muon #Neutrino Physics Research #Nuclear physics #Nuclear physics research studies #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #Spectral line #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.105.053006
published as Phys. Rev. D 105, 053006 (2022) · 13 pages, matches PRD version; table included as ancillary file
arxiv created 2022/03/18 · openalex publication_date 2022/03/18 · arxiv updated 2022/03/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
The decay μ-→ e- νeνμ of a muon that is bound to a nucleus poses an unavoidable background for experiments such as Mu2e, COMET, and DeeMe searching for lepton-flavor-violating μ-→ e- conversion and thus requires a precise understanding. We calculate the electron-energy spectra of muon decays in orbit near the electron energy endpoint for all stable isotopes and estimate uncertainties due to the nuclear charge distribution. Our results enable background studies of mixed or enriched target materials that are necessary for the next generation of μ-→ e- conversion experiments.