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Improved Calculation of Electroweak Radiative Corrections and the Value of V_ud

William J. Marciano·Alberto Sirlin
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Abstract

A new method for computing hadronic effects on electroweak radiative corrections to low-energy weak interaction semileptonic processes is described. It employs high order perturbative QCD results originally derived for the Bjorken sum rule along with a large N QCD-motivated interpolating function that matches long and short-distance loop contributions. Applying this approach to the extraction of the CKM matrix element V_ud from superallowed nuclear beta decays reduces the theoretical loop uncertainty by about a factor of 2 and gives V_ud = 0.97377(11)(15)(19). Implications for CKM unitarity are briefly discussed.

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William J. Marciano, Alberto Sirlin. 2005-10-18. Improved Calculation of Electroweak Radiative Corrections and the Value of V_ud. https://doi.org/10.1103/physrevlett.96.032002

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