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Top mass determination and O (alpha_S^5 m) correction to toponium 1S energy level

Y. Kiyo·Y. Sumino
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Abstract

Recently the full O(alpha_S^5 m, alpha_S^5 m log(alpha_S)) correction to the heavy quarkonium 1S energy level has been computed (except the a_3-term in the QCD potential). We point out that the full correction (including the log(alpha_S)-term) is approximated well by the large-beta_0 approximation. Based on the assumption that this feature holds up to higher orders, we discuss why the top quark pole mass cannot be determined to better than O(Lambda_{QCD}) accuracy at a future e^+e^- collider, while the MS-bar mass can be determined to about 40 MeV accuracy (provided the 4-loop MSbar-pole mass relation will be computed in due time).

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Y. Kiyo, Y. Sumino. 2003-02-16. Top mass determination and O (alpha_S^5 m) correction to toponium 1S energy level. https://doi.org/10.1103/physrevd.67.071501

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