Four-loop moments of the heavy quark vacuum polarization function in perturbative QCD
نویسنده
چکیده
New results at four-loop order in perturbative QCD for the first two Taylor coefficients of the heavy quark vacuum polarization function are presented. They can be used to perform a precise determination of the charmand bottom-quark mass. Implications for the value of the quark masses are briefly discussed. PACS. 12.38.Bx Perturbative calculations – 12.38.-t Quantum chromodynamics – 11.55.Fv Dispersion relations – 14.65.Dw Charmed quarks – 14.65.Fy Bottom quarks
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