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arXiv · 1707.03964

Hadronic tau decays and the strong coupling

Diogo Boito·Maarten Golterman·Kim Maltman·Santiago Peris
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Abstract

We provide an overview of recent determinations of the strong coupling, $α_s$, from hadronic $τ$ decays. We contrast two analysis methods, the "truncated-OPE approach" and the "DV-model approach," highlighting the assumptions going into each of these. We argue that a detailed study based on ALEPH data shows the truncated-OPE approach to be quantitatively unreliable, while the DV-model approach passes all tests. New data for hadronic $τ$ decays from Belle and Belle-II could provide more stringent tests of the DV-model approach, and thus potentially lead to a more precise value of $α_s$ from hadronic $τ$ decays.

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Diogo Boito, Maarten Golterman, Kim Maltman, Santiago Peris. 2017-07-13. Hadronic tau decays and the strong coupling. https://doi.org/10.1088/1742-6596%2F912%2F1%2F012003

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