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A new determination of the QED coupling alpha(M_Z^2) lets the Higgs off the hook

A. D. Martin·J. Outhwaite·M. G. Ryskin
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Abstract

We use the available data on e+ e- -> hadrons to determine the value of the QED coupling at the Z pole. The inclusion of recent preliminary BES-II data in the analysis is found to reduce the ambiguity in the determination of the coupling, particularly that arising from the use of either exclusive or inclusive data in the energy region \sqrt{s} < 2 GeV, in favour of a larger value of α(M_Z^2)^{-1} = 128.978 +/- 0.027. As a consequence the predicted value of the mass of the (Standard Model) Higgs boson is increased, so that the preferred value is just above the LEP2 bound.

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A. D. Martin, J. Outhwaite, M. G. Ryskin. 2000-09-14. A new determination of the QED coupling alpha(M_Z^2) lets the Higgs off the hook. https://doi.org/10.1016/s0370-2693(00)01083-2

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