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arXiv · hep-ph/0312148

The electric charge at the two-loop level in the Standard Model and the precision measurements of Delta alpha_{had}

Abstract

The complete calculation of the 2-loop electroweak corrections to the renormalization of the electric charge in the Standard Model allows to discuss in detail the value of the MSbar effective coupling $\hat e(m_Z)$. We discuss the phenomenological impact of these results in view of the increasing accuracy in the measurements of the cross-section of the reaction e+e- -->hadrons at low energies.

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Alessandro Vicini. 2003-12-16. The electric charge at the two-loop level in the Standard Model and the precision measurements of Delta alpha_{had}. https://doi.org/10.1016/s0920-5632(04)00018-0

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