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Total decay rate of a muon bound to a light nucleus

A. Czarnecki1,*, A. O. Davydov1, and M. Y. Kaygorodov2

  • *Contact author: andrzejc@ualberta.ca
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Phys. Rev. D 113, 036028 – Published 26 February, 2026

DOI: https://doi.org/10.1103/38ly-8srx

Abstract

We revisit the total decay rate of a muon being in the ground state of a Coulomb potential with atomic charge numbers 4≤Z≤9. The discrepancy between the perturbative (αZ)2 result in H. Überall [Phys. Rev. 119, 365 (1960)] and the fully relativistic partial-wave calculation of R. Watanabe et al. [At. Data Nucl. Data Tables 54, 165 (1993)] for oxygen (Z=8) is shown to originate from insufficient convergence of the partial-wave series in the latter work. Our accurate relativistic calculations restore agreement with the perturbative αZ expansion and indicate a negative sign for the next-order (αZ)3 correction.

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Phys. Rev. D 113, 036028– Published 26 February, 2026
  • Received 5 January 2026
  • Accepted 6 February 2026
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