اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدImproved measurement of the $pi rightarrow mbox{e} u$ branching ratio
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A new measurement of the branching ratio, $R_{e/mu} =Gamma (pi^+ rightarrow mbox{e}^+ u + pi^+ rightarrow mbox{e}^+ u gamma)/ Gamma (pi^+ rightarrow mu^+ u + pi^+ rightarrow mu^+ u gamma)$, resulted in $R_{e/mu}^{exp} = (1.2344 pm 0.0023 (stat) pm 0.0019 (syst)) times 10^{-4}$. This is in agreement with the standard model prediction and improves the test of electron-muon universality to the level of 0.1 %.
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