@misc{10481/29034,
year = {2008},
url = {http://hdl.handle.net/10481/29034},
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^r(M_rho) and C_87^r(M_rho). These two low-energy constants 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 L_10^r(M_rho) = -(5.22\pm 0.06)10^{-3}. Including in the analysis the two-loop (order p^6) contributions, we get L_10^r(M_rho) = -(4.06\pm 0.39)10^{-3} and C_87^r(M_rho) = (4.89\pm 0.19)10^{-3}GeV^{-2}. In the SU(2) chiral effective theory, the corresponding low-energy coupling takes the value \overline l_5 = 13.30 \pm 0.11 at order p^4, and \overline l_5 = 12.24 \pm 0.21 at order p^6.},
publisher = {American Physical Society},
keywords = {Strange quark mass},
keywords = {Low-energy constants},
keywords = {Us-vertical-bar},
keywords = {Perturbation theory},
keywords = {Spectral functions},
keywords = {QCD predictions},
keywords = {Hadronic width},
title = {Determination of the Chiral Couplings L10 and C87 from Semileptonic τ Decays},
author = {González-Alonso, Martín and Pich, Antonio and Prades, Joaquim},
}