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Electromagnetic radiative corrections to pionic beta decay π^+ to π^0 e^+ ν_e

Hannes Pichl
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Abstract

Pionic beta decay π^+ to π^0 e^+ ν_e is analyzed in chiral perturbation theory with virtual photons and leptons. All electromagnetic corrections up to order e^2 p^2 are taken into account. Theoretical results are confronted with preliminary data from a PSI measurement and a value for the CKM matrix element |Vud| is given. Although the precision is presently still below the one of existing determinations of |Vud|, an analysis of pionic beta decay, based on a systematic treatment within a low-energy effective field theory, may become a useful alternative.

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Hannes Pichl. 2002-09-25. Electromagnetic radiative corrections to pionic beta decay π^+ to π^0 e^+ ν_e. https://doi.org/10.1016/s0920-5632(03)01844-9

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