arXiv subjects

Stefan Bekavac

Publications and source records attributed to Stefan Bekavac.

2 recordsLinked to original sources

arXiv2007

On-shell renormalisation constants including two different nonzero masses

We present results for the effect of a second massive quark in the relation between the pole and the minimal subtracted quark mass at the three loop level. We also consider the analogous effect for the wave function renormalisation constant. Some technical details of the calculation are given. Our result is phenomenologically relevant for the bottom quark including virtual charm effects.

hep-ph↗

arXiv2006

Calculation of Massless Feynman Integrals using Harmonic Sums

A method for the evaluation of the epsilon expansion of multi-loop massless Feynman integrals is introduced. This method is based on the Gegenbauer polynomial technique and the expansion of the Gamma function in terms of harmonic sums. Algorithms for the evaluation of nested and harmonic sums are used to reduce the expressions to get analytical or numerical results for the expansion coefficients. Methods to increase the precision of numerical results are discussed.

hep-ph↗