New Precise Measurement of the Pion Weak Form Factors inπ+→e+νγDecay
نویسندگان
چکیده
منابع مشابه
N ov 2 00 3 A new evaluation of the pion weak form factors
We have used the PIBETA large acceptance detector for a precise measurement of the π + → e + νγ radiative decay at rest, with broad phase space coverage. Using the CVC value for the pion vector form factor, F V = 0.0259(5), we have obtained a new value of the pion axial-vector form factor γ = F A /F V = 0.429(14). However, significant deviations from the SM predictions are evident in our data. ...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2009
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.103.051802