Next - to - next - to - leading order vacuum polarization function of heavy quark near threshold and sum rules for bb̄ system
نویسندگان
چکیده
Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for b ¯ b system. Abstract A correlator of the vector current of a heavy quark is computed analytically near threshold in the next-to-next-to-leading order in perturbative and relativistic expansion that includes α 2 s , α s v and v 2 corrections in the coupling constant and velocity of the heavy quark to the nonrelativistic Coulomb approximation. Based on this result, the numerical values of the b-quark pole mass and the strong coupling constant are determined from the analysis of sum rules for the Υ system.
منابع مشابه
Vacuum Polarization Function of Heavy Quark near Threshold and Sum Rules for B B System in the Next-to-next-to-leading Order
A correlator of the vector current of a heavy quark is computed analytically near threshold in the next-to-next-to-leading order in per-turbative and relativistic expansion that includes 2 s , s v and v 2 corrections in the coupling constant and velocity of the heavy quark to the nonrelativistic Coulomb approximation. Based on this result, the numerical values of the b-quark pole mass and the s...
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