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arXiv · hep-ph/0403083

MSbar Charm Mass from Charmonium Sum Rules with Contour Improvement

Abstract

A detailed error analysis is carried out for the determination of the MSbar charm quark mass $\bar m_c(\bar m_c)$ from moments at order alpha_s^2 of the charm cross section in e^+e^- annihilation. To estimate the theoretical uncertainties the renormalization scale is implemented in various ways including energy-dependent functions, which lead to ``contour-improved'' predictions. We obtain $\bar m_c(\bar m_c)=1.29\pm 0.07$ GeV which contains a substantial theoretical uncertainty.

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BibTeXRIS

A. H. Hoang, M. Jamin. 2004-03-08. MSbar Charm Mass from Charmonium Sum Rules with Contour Improvement. https://doi.org/10.1016/j.physletb.2004.04.080

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