Determination of beyond NNLO using event shape averages

Adam Kardos; Gábor Somogyi; Andrii Verbytskyi

doi:10.1140/epjc/s10052-021-08975-3

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2024 Impact factor 4.8

Particles and Fields

Open Access

Eur. Phys. J. C (2021) 81: 292
https://doi.org/10.1140/epjc/s10052-021-08975-3

Regular Article - Theoretical Physics

Determination of $α_{S}$ $\alpha _{S}$ beyond NNLO using event shape averages

Adam Kardos¹, Gábor Somogyi² and Andrii Verbytskyi³^c

¹ University of Debrecen, PO Box 105, 4010, Debrecen, Hungary
² ELKH-DE Particle Physics Research Group, PO Box 105, 4010, Debrecen, Hungary
³ Max-Planck-Institut für Physik, 80805, Munich, Germany

^c andrii.verbytskyi@mpp.mpg.de

Received: 28 September 2020
Accepted: 13 February 2021
Published online: 7 April 2021

Abstract

We consider a method for determining the QCD strong coupling constant using fits of perturbative predictions for event shape averages to data collected at the LEP, PETRA, PEP and TRISTAN colliders. To obtain highest accuracy predictions we use a combination of perturbative $O (α_{S}^{3})$ ${{{\mathcal {O}}}}(\alpha _{S}^{3})$ calculations and estimations of the $O (α_{S}^{4})$ ${{{\mathcal {O}}}}(\alpha _{S}^{4})$ perturbative coefficients from data. We account for non-perturbative effects using modern Monte Carlo event generators and analytic hadronization models. The obtained results show that the total precision of the $α_{S}$ $\alpha _{S}$ determination cannot be improved significantly with the higher-order perturbative QCD corrections alone, but primarily requires a deeper understanding of the non-perturbative effects.

© The Author(s) 2021

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