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arXiv · 1001.0389

Alpha_s Determination from Tau Decays: Theoretical Status

Antonio Pich
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Abstract

The total tau hadronic width can be accurately calculated using analyticity and the operator product expansion. The result turns out to be very sensitive to the value of alpha_s(m_tau^2), providing a precise determination of the strong coupling constant. The theoretical description of this observable is updated, including the recently computed O(alpha_s^4) contributions. The experimental determination of alpha_s(m_tau^2) and its actual uncertainties are discussed.

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Antonio Pich. 2010-01-03. Alpha_s Determination from Tau Decays: Theoretical Status. https://arxiv.org/abs/1001.0389

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