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  • Open Access

Muon-Decay Parameters from COHERENT

Víctor Bresó-Pla1,*, Sergio Cruz-Alzaga2,†, Martín González-Alonso2,‡, and Suraj Prakash2,§

  • *Contact author: breso@thphys.uni-heidelberg.de
  • †Contact author: alzaga@ific.uv.es
  • ‡Contact author: martin.gonzalez@ific.uv.es
  • §Contact author: suraj.prakash@ific.uv.es
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Phys. Rev. Lett. 135, 131802 – Published 22 September, 2025

DOI: https://doi.org/10.1103/mlhl-v822

Abstract

We demonstrate that measurements of coherent elastic neutrino-nucleus scattering at spallation sources are valuable probes of muon-decay physics. Using COHERENT data we derive the first direct constraint on the Michel parameters governing the ν¯μ energy distribution. We also discuss future sensitivities, the implications for the Lorentz structure of the interactions mediating muon decay, and the application to other neutrino-production mechanisms like pion decay.

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Phys. Rev. Lett. 135, 131802– Published 22 September, 2025
  • Received 12 March 2025
  • Accepted 14 August 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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