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We include two loop, relativistic one loop and second order relativistic treelevel corrections, plus leading nonperturbative contributions, to obtain acalculation of the lower states in the heavy quarkonium spectrum correct up to,and including, $O(\alpha_s^4)$ and leading $\Lambda^4/m^4$ terms. This allowsus, in particular, to obtain a model independent determination of the polemasses of the $b, c$ quarks, $$m_b=5 015^{+110}_{-70} mev; m_c=1884^{+222}_{-133} mev$$ to which correspond the $\bar{\hbox{MS}}$ masses,$$\bar{m}_b(\bar{m}_b^2)=4 453^{+50}_{-32} mev; \bar{m}_c(\bar{m}_c^2)=1547^{+169}_{-102} mev.$$ The decay $\Gamma(\Upsilon\to e^+e^-)$ is found inagreement with experiment, $$\Gamma(\Upsilon\to e^+e^-)=1.135^{+0.27}_{-0.29}kev (\hbox{exp.}=1.320\pm0.04 kev),$$ and the hyperfine splitting is predictedto be $$M(\Upsilon)-M(\eta)=48.5^{+15.7}_{-12.2} mev.$$Comment: Plain TeX fil

physical review. d. particles, fields, gravitation, and cosmology/physical review. d. particles and fields

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Calculation of the quarkonium spectrum andmb,mcto order