Event shapes in $e^+e^-$ annhilation at NNLO

TL;DR

This paper presents the first NNLO calculations of event shape distributions in electron-positron annihilation, showing significant corrections that improve agreement with experimental data.

Contribution

First NNLO theoretical predictions for event shape distributions in $e^+e^-$ annihilation, enhancing precision and comparison with experiments.

Findings

NNLO corrections are sizeable for all variables.

Inclusion of NNLO improves agreement with experimental data.

Corrections vary significantly among different observables.

Abstract

We report first results on the calculation of NNLO corrections to event shape distributions in electron-positron annhilation. The corrections are sizeable for all variables, however their magnitude is substantially different for different observables. We observe that inclusion of the NNLO corrections yields a considerably better agreement between theory and experimental data both in shape and normalisation of the event shape distributions.