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arXiv · hep-ph/0610206

Four-loop beta function and mass anomalous dimension in Dimensional Reduction

R. V. Harlander·D. R. T. Jones·P. Kant·L. Mihaila·M. Steinhauser
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Abstract

Within the framework of QCD we compute renormalization constants for the strong coupling and the quark masses to four-loop order. We apply the DR-bar scheme and put special emphasis on the additional couplings which have to be taken into account. This concerns the epsilon-scalar--quark Yukawa coupling as well as the vertex containing four epsilon-scalars. For a supersymmetric Yang Mills theory, we find, in contrast to a previous claim, that the evanescent Yukawa coupling equals the strong coupling constant through three loops as required by supersymmetry.

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R. V. Harlander, D. R. T. Jones, P. Kant, L. Mihaila, M. Steinhauser. 2007-06-22. Four-loop beta function and mass anomalous dimension in Dimensional Reduction. https://doi.org/10.1088/1126-6708%2F2006%2F12%2F024

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