Journal of High Energy Physics

, 2016:53 | Cite as

Direct measurement of αQED(m Z 2 ) at the FCC-ee

  • Patrick Janot
Open Access
Regular Article - Experimental Physics


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 Z 2 ). 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 Z 2 ) with an accuracy deemed adequate for an optimal use of the FCC-ee precision data.


Electroweak interaction e+-e- Experiments 


Open Access

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Copyright information

© The Author(s) 2016

Authors and Affiliations

  1. 1.CERN, EP DepartmentGenevaSwitzerland

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