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arXiv · 1210.0325

World Summary of $α_s$ (2012)

Siegfried Bethke
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Abstract

Determinations of the strong coupling strength, $α_s$, are summarised and a new world average value of $α_s (M_Z)$ is determined, using a new method of pre-averaging results within classes of measurements like hadronic $τ$ decays, deep inelastic scattering processes, lattice calculations, electron-positron annihilation processes and electro-weak precision fits. The overall result is $$α_s (M_Z) = 0.1184 \pm 0.0007,$$ unchanged from the value obtained in 2009. This presentation is an excerpt from the QCD review section of the 2012 Review of Particle Physics (RPP) of the Particle Data Group.

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Siegfried Bethke. 2012-10-01. World Summary of $α_s$ (2012). https://doi.org/10.1016/j.nuclphysbps.2012.12.020

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