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arXiv · 1509.08494

ChPT parameters from tau-decay data

A. Rodríguez-Sánchez·M. González-Alonso·A. Pich
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Abstract

Using the updated ALEPH V-A spectral function from tau decays, we determine the lowest spectral moments of the left-right correlator and extract dynamical information on order parameters of the QCD chiral symmetry breaking. Uncertainties associated with violations of quark-hadron duality are estimated from the data, imposing all known short-distance constraints on a resonance-based parametrization. Employing proper pinched weight functions, we obtain an accurate determination of the effective chiral couplings L10 and C87 and the dimension-six and -eight contributions in the Operator Product Expansion.

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A. Rodríguez-Sánchez, M. González-Alonso, A. Pich. 2015-09-28. ChPT parameters from tau-decay data. https://arxiv.org/abs/1509.08494

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