Determination of the strong-coupling constant from the $Z$-boson transverse-momentum distribution

TL;DR

This paper determines the strong-coupling constant by analyzing the low-momentum region of Z-boson transverse-momentum distributions using third-order perturbative QCD predictions and CDF data.

Contribution

It provides a novel extraction of the strong coupling constant from Z-boson transverse-momentum data at third-order perturbative QCD.

Findings

Measured alpha_S(m_Z) = 0.1191 with uncertainties

Uses third-order perturbative QCD predictions

Analyzes CDF proton-proton collision data

Abstract

The strong-coupling constant is determined from the low-momentum region of the transverse-momentum distribution of $Z$ bosons produced through the Drell-Yan process, using predictions at third order in perturbative QCD. The analysis employs a measurement performed in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 1.96$ TeV with the CDF experiment. The determined value of the strong coupling at the reference scale corresponding to the $Z$-boson mass is $\alpha_S(m_Z) = 0.1191^{+0.0013}_{-0.0016}$.