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arXiv · 1512.05544

Direct measurement of alpha_QED(mZ) at the FCC-ee

Patrick Janot
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Abstract

When the measurements from the FCC-ee become available, an improved determination of the standard-model "input" parameters will be needed to fully exploit the new precision data towards either constraining or fitting the parameters of beyond-the-standard-model theories. Among these input parameters is the electromagnetic coupling constant estimated at the Z mass scale, alpha_QED(mZ). The measurement of the muon forward-backward asymmetry at the FCC-ee, just below and just above the Z pole, can be used to make a direct determination of alpha_QED(mZ) with an accuracy deemed adequate for an optimal use of the FCC-ee precision data.

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Patrick Janot. 2017-11-21. Direct measurement of alpha_QED(mZ) at the FCC-ee. https://doi.org/10.1007/jhep02(2016)053

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