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arXiv · 0810.2459

Chiral low-energy constants L_10 and C_87 from hadronic tau decays

Martin Gonzalez-Alonso·Antonio Pich·Joaquim Prades
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Abstract

Using recent precise hadronic tau-decay data on the V-A spectral function and general properties of QCD such as analyticity, the operator product expansion and chiral perturbation theory, we get accurate values for the QCD chiral order parameters L_10 and C_87. At order p^4 we obtain L_10^r(M_rho)=-(5.22+-0.06)10^-3, whereas at order p^6 we get L_10^r(M_rho)=-(4.06+-0.39)10^-3 and C_87^r(M_rho) = (4.89+-0.19)10^-3 GeV^-2.

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Martin Gonzalez-Alonso, Antonio Pich, Joaquim Prades. 2008-10-16. Chiral low-energy constants L_10 and C_87 from hadronic tau decays. https://doi.org/10.1016/j.nuclphysbps.2008.12.040

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