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arXiv · 0812.1943

From hadronic tau decays to the chiral couplings L_10 and C_87

M. Gonzalez-Alonso·A. Pich·J. Prades
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Abstract

A sum rule analysis of the hadronic tau-decay data can be used to determine the low-energy constants L10(mu) and C87(mu). These constants are QCD chiral-order parameters, which appear at order p^4 and p^6, respectively, in the chiral perturbation theory expansion of the V-A correlator. At order p^4 we obtain L10(M_rho) = -(5.22\pm 0.06)10^-3. Including in the analysis the order p^6 contributions, we get L10(M_rho) = -(4.06\pm 0.39)10^-3 and C87(M_rho) = (4.89\pm 0.19)10^-3 GeV^-2.

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M. Gonzalez-Alonso, A. Pich, J. Prades. 2008-12-10. From hadronic tau decays to the chiral couplings L_10 and C_87. https://doi.org/10.1016/j.nuclphysbps.2009.03.017

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