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arXiv · 0705.0028

Pion Leptonic Decays and Supersymmetry

Michael Ramsey-Musolf·Shufang Su·Sean Tulin
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Abstract

We compute supersymmetric contributions to pion leptonic (π_{l2}) decays in the Minimal Supersymmetric Standard Model (MSSM). When R-parity is conserved, the largest contributions to the ratio R_{e/μ} = Γ[ π^+ \to e^+ ν_e(γ)]/Γ[ π^+ \to μ^+ ν_μ(γ)] arise from one-loop (V-A)x(V-A) corrections. These contributions can be potentially as large as the sensitivities of upcoming experiments; if measured, they would imply significant bounds on the chargino and slepton sectors complementary to current collider limits. We also analyze R-parity violating interactions, which may produce a detectable deviation in R_{e/μ} while remaining consistent with all other precision observables.

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Michael Ramsey-Musolf, Shufang Su, Sean Tulin. 2007-06-24. Pion Leptonic Decays and Supersymmetry. https://doi.org/10.1103/physrevd.76.095017

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