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, αQED(m 2 Z ). The measurement of the muon forwardbackward asymmetry at the FCC-ee, just below and just above the Z pole, can be used to make a direct determination of αQED(m 2 Z ) with an accuracy deemed adequate for an optimal use of the FCC-ee precision data.
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ArXiv ePrint: 1512.05544
An erratum to this article is available at https://doi.org/10.1007/JHEP11(2017)164.
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Janot, P. Direct measurement of αQED(m 2 Z ) at the FCC-ee. J. High Energ. Phys. 2016, 53 (2016). https://doi.org/10.1007/JHEP02(2016)053
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DOI: https://doi.org/10.1007/JHEP02(2016)053