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Muon transverse polarization in the $K_{l2γ}$ decay in SM

V. V. Braguta·A. E. Chalov·A. A. Likhoded
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Abstract

The muon transverse polarization in the $K^+ \to μ^+ νγ$ process induced by the electromagnetic final state interaction is calculated in the framework of Standard Model. It is shown that one loop contributions lead to a nonvanihing muon transverse polarization. The value of the muon transverse polarization averaged over the kinematical region of $E_γ\geq 20$ MeV is equal to $5.63 \times 10^{-4}$.

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V. V. Braguta, A. E. Chalov, A. A. Likhoded. 2002-05-18. Muon transverse polarization in the $K_{l2γ}$ decay in SM. https://doi.org/10.1103/physrevd.66.034012

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