Momentum subtraction and the R-ratio

TL;DR

This paper calculates the R-ratio for massless quarks across different renormalization schemes and loop orders, analyzing how scheme choices affect the ratio's behavior.

Contribution

It provides detailed computations of the R-ratio in multiple renormalization schemes up to various loop orders, highlighting scheme dependence.

Findings

R-ratio computed for several schemes and loop orders

Scheme dependence of the R-ratio analyzed

Results facilitate comparisons across renormalization schemes

Abstract

We determine the R-ratio for massless quarks in several renormalization schemes to various loop orders. These are the momentum subtraction schemes of Celmaster and Gonsalves as well as the minimal momentum subtraction scheme. The dependence of the R-ratio on the schemes is analysed.