$\sigma (e^{+}{e}^{-}\to hadrons)$ and the Heavy Quark Masses

Abstract

The precise data for the total cross section $\sigma (e^{+}{e}^{-}\to hadrons)$ from the charm threshold region, when combined with the evaluation of moments with three loop accuracy, lead to a direct determination of the short distance $\overline{\mathrm{MS}}$ charm quark mass $m_c(m_c)=1.304(27)$. Applying the same approach to the bottom quark we obtain $m_b(m_b)=4.191(51)$ GeV. A complementary method for the determination of $m_b$ is based of the analysis of the ${\rm Y}(1S)$ system which is confronted with a next-to-next-to-next-to-leading order calculation of the corresponding energy level. This leads to $m_b(m_b)=4.346(70)$ GeV.

Comments: 5 pages, talk presented at RADCOR/Loops and Legs 2002