m_u + m_d from QCD-Hadron Duality

Abstract

The value of the light quark masses combination $m_u+m_d$ is analized using QCD-Hadron Duality. A detailed analysis of both the perturbative QCD [to four-loops] and the hadronic parametrization needed is done. The result we get is $[m_u+m_d](1Ge{V}^2)=(12.8\pm 2.5)$ MeV ($[m_u+m_d](4Ge{V}^2)=(9.8\pm 1.9)$ MeV) in the $\text{barMS}$ scheme.

Comments: 9 pages, LaTeX, 2 ps figures, uses epsf.sty. To be published in Proceedings of the ``High Energy Conference on Quantum Chromodynamics (QCD '97)'', 3-9 July 1997, Montpellier, France