Renormalization group improvement and QCD sum rules

Abstract

We summarize the results obtained for the quark masses (u,d,s,c, and b) in Refs. [1,2] and strong coupling (αs) using renormalization group (RG) improvement of the theoretical expressions and experimental inputs that enter in the QCD sum rules. We obtain mu(2GeV)=2.00−0.40+0.33MeV, md(2GeV)=4.21−0.45+0.48MeV, and ms(2GeV)=104.34−4.24+4.32MeV using Borel Laplace sum rules for the divergence of the axial vector currents. The relativistic sum rules for the moments of the heavy quark currents lead to the determination of αs(MZ)=0.1171(7), m‾c=1281.1(3.8)MeV and m‾b=4174.3(9.5)MeV.