Improvement of W Boson Hadronic Decay Width up to $\mathcal{O}\left(\alpha_s^4 \right)$-order

TL;DR

This paper applies the principle of maximum conformality to improve the precision of the W boson's hadronic decay width calculation by incorporating four-loop level pQCD corrections, reducing scale uncertainties.

Contribution

It introduces a PMC-based method to accurately determine the W boson decay width at four-loop order, minimizing renormalization scale dependence.

Findings

PMC reduces scale dependence in decay width calculations.

Four-loop pQCD corrections significantly improve prediction accuracy.

Method enables indirect determination of charm-strange mixing parameter.

Abstract

The principle of maximum conformality (PMC) is used to remove uncertainties in the renormalization scale and scheme, thus eliminating unnecessary systematic errors for high-precision perturbative Quantum Chromodynamics (pQCD) predictions. In this work, we use PMC method to improve the determination of the decay width of the $W$ boson in hadrons by working on the corrections coming from pQCD theory at the four-loop level. In conventional scale setting, we find that the initial scaling dependence of the renormalization is small only at high correction orders, whereas in single-scale PMC method we obtain a scaling-independent initial result. Finally, the wide hadronic decay of $W$ is used for an indirect determination of the charm-strange mixing parameter.