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Global analysis of muon decay measurements

C. A. Gagliardi·R. E. Tribble·N. J. Williams
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Abstract

We have performed a global analysis of muon decay measurements to establish model-independent limits on the space-time structure of the muon decay matrix element. We find limits on the scalar, vector and tensor coupling of right- and left-handed muons to right- and left-handed electrons. The limits on those terms that involve the decay of right-handed muons to left-handed electrons are more restrictive than in previous global analyses, while the limits on the other non-standard model interactions are comparable. The value of the Michel parameter eta found in the global analysis is -0.0036 \pm 0.0069, slightly more precise than the value found in a more restrictive analysis of a recent measurement. This has implications for the Fermi coupling constant G_F.

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C. A. Gagliardi, R. E. Tribble, N. J. Williams. 2005-09-07. Global analysis of muon decay measurements. https://doi.org/10.1103/physrevd.72.073002

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