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Calculation of $\barα_{\rm Q.E.D.}$ on the Z

J. F. de Troconiz·F. J. Yndurain
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Abstract

We perform a new, detailed calculation of the hadronic contributions to the running electromagnetic coupling, $\barα$, defined on the Z particle (91 GeV). We find for the hadronic contribution, including radiative corrections, $$10^5\times \deltav_{\rm had.}α(M_Z^2)= 2740\pm12,$$ or, excluding the top quark contribution, $$10^5\times \deltav_{\rm had.}α^{(5)}(M_Z^2)= 2747\pm12.$$ Adding the pure QED corrections we get a value for the running electromagnetic coupling of $$\barα_{\rm Q.E.D.}(M_Z^2)= {{1}\over{128.965\pm0.017}}.$$

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J. F. de Troconiz, F. J. Yndurain. 2002-01-11. Calculation of $\barα_{\rm Q.E.D.}$ on the Z. https://doi.org/10.1103/physrevd.65.093002

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