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Asymptotic Pade Approximant Predictions: up to Five Loops in QCD and SQCD

J. Ellis·I. Jack·D. R. T. Jones·Marek Karliner·Mark A. Samuel
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Abstract

We use Asymptotic Pade Approximants (APAP's) to predict the four- and five-loop β-functions in QCD and N=1 supersymmetric QCD (SQCD), as well as the quark mass anomalous dimensions in Abelian and non-Abelian gauge theories. We show how the accuracy of our previous β-function predictions at the four-loop level may be further improved by using estimators weighted over negative numbers of flavours (WAPAP's). The accuracy of the improved four-loop results encourages confidence in the new five-loop β-function predictions that we present. However, the WAPAP approach does not provide improved results for the anomalous mass dimension, or for Abelian theories.

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J. Ellis, I. Jack, D. R. T. Jones, Marek Karliner, Mark A. Samuel. 1997-11-15. Asymptotic Pade Approximant Predictions: up to Five Loops in QCD and SQCD. https://doi.org/10.1103/physrevd.57.2665

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