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Title: The pion beta and radiative electronic decays
As the lightest meson, pion offers unique opportunities for measuring parameters and testing limits of the Standard Model (SM). The PiBeta experiment, carried out at PSI, focused on SM tests accessible through the pion beta, \pi^+ \to \pi^0e^+\nu_e(\gamma) π + → π 0 e + ν e ( γ ) , and electronic radiative, \pi^+ \to e^+\nu_e\gamma π + → e + ν e γ , decay channels. We review the PiBeta experiment, and update the pion beta decay branching ratio B^{\text{exp}}_{\pi\beta}=1.038(6)_{\text{tot}}\times10^{-8} B π β exp = 1.038 ( 6 ) tot × 10 − 8 , along with the corresponding derived value of the Cabibbo-Kobayashi-Maskawa matrix element V_{ud} = 0.9738(28) V u d = 0.9738 ( 28 ) .  more » « less
Award ID(s):
1913957
NSF-PAR ID:
10333446
Author(s) / Creator(s):
Date Published:
Journal Name:
SciPost Physics Proceedings
Issue:
5
ISSN:
2666-4003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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