A Simple Way to Estimate the Value of $\barα\equivα(m^2_Z)$

R. B. Nevzorov; A. V. Novikov; M. I. Vysotsky

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A Simple Way to Estimate the Value of $\barα\equivα(m^2_Z)$

R. B. Nevzorov·A. V. Novikov·M. I. Vysotsky

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Abstract

To obtain the value of electromagnetic coupling constant at $q^2=m^2_Z$, $\barα$, which plays a key role in electroweak physics one has to integrate the cross-section of $e^+e^-$-annihilation into hadrons divided by $(s-m^2_Z)$ over $s$ from threshold to infinity. By combining, for each flavor channel, the contribution of lowest resonance with the perturbative QCD continuum, we obtain $1/\barα = 128.90\pm 0.06 $ a result which is close to known result obtained with purely experimental inputs, i.e. $1/\barα = 128.87\pm 0.12$.

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R. B. Nevzorov, A. V. Novikov, M. I. Vysotsky. 1994-05-26. A Simple Way to Estimate the Value of $\barα\equivα(m^2_Z)$. https://arxiv.org/abs/hep-ph/9405390

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