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arXiv · hep-ph/0103047

Low-energy gluon contributions to the vacuum polarization of heavy quarks

S. Groote·A. A. Pivovarov
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Abstract

We calculate a correction to the electromagnetic current induced by a heavy quark loop. The contribution of this correction to the vacuum polarization function appears at the O(alpha_s^3) order of perturbation theory and has a qualitatively new feature -- its absorptive part starts at zero energy in contrast to other contributions where the absorptive parts start at the two-particle threshold. Our result imposes a constraint on the order n of the moments used in the heavy-quark sum rules, n<4.

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S. Groote, A. A. Pivovarov. 2001-03-05. Low-energy gluon contributions to the vacuum polarization of heavy quarks. https://doi.org/10.1134/1.1478517

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