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Renormalon contributions to δρ

Paolo Gambino·Alberto Sirlin
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Abstract

Leading QCD vacuum polarization contributions to the electroweak parameter $δρ$ are evaluated numerically using several different prescriptions for the gluon self-energy. Simple theoretical estimates of the asymptotic behavior are given. The results show a significant contribution from the leading infrared renormalons when $δρ$ is expressed in terms of the top-quark pole mass and its absence when the $\msbar$ running mass is employed. The calculations are applied to estimate higher order QCD contributions to $δρ$.

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Paolo Gambino, Alberto Sirlin. 1995-05-30. Renormalon contributions to δρ. https://doi.org/10.1016/0370-2693(95)00741-3

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