Measurement of the strong coupling alpha_S from the three-jet rate in e+e- - annihilation using JADE data

TL;DR

This paper measures the strong coupling constant alpha_S at various energies using three-jet rates from e+e- annihilation data, employing advanced theoretical predictions to achieve a precise determination consistent with the world average.

Contribution

It provides a new measurement of alpha_S using next-to-next-to-leading order predictions matched with logarithmic approximations, based on JADE data at energies between 14 and 44 GeV.

Findings

Measured alpha_S(MZ) = 0.1199 with uncertainties.

Results are consistent with the world average.

Demonstrates the effectiveness of NNLO predictions in alpha_S extraction.

Abstract

We present a measurement of the strong coupling alpha_S using the three-jet rate measured with the Durham algorithm in e+e- -annihilation using data of the JADE experiment at centre-of-mass energies between 14 and 44 GeV. Recent theoretical improvements provide predictions of the three-jet rate in e+e- -annihilation at next-to-next-to-leading order. In this paper a measurement of the three-jet rate is used to determine the strong coupling alpha_s from a comparison to next-to-next-to-leading order predictions matched with next-to-leading logarithmic approximations and yields a value for the strong coupling alpha_S(MZ) = 0.1199+- 0.0010 (stat.) +- 0.0021 (exp.) +- 0.0054 (had.) +- 0.0007 (theo.) consistent with the world average.