Light Quark Masses from QCD

Abstract

We study the value of the light quark masses combination $m_u+m_d$ in QCD using both Finite Energy Sum Rules and Laplace Sum Rules. We have performed a detailed analysis of both the perturbative QCD and the hadronic parametrization inputs needed in these Sum Rules. As main result, we obtain $m_u\left(1{\mathrm{GeV}}^2\right)+m_d\left(1{\mathrm{GeV}}^2\right)=\left(12\pm 2.5\right)\mathrm{MeV}$ for the running $\overline{MS}$ masses.

Comments: 17 pages, LaTeX, 5 postscript figures included, uses cite.sty(included) and epsf.sty