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arXiv · 0806.4601

e^+ e^- -> 3 jets and event shapes at NNLO

G. Dissertori·A. Gehrmann-De Ridder·T. Gehrmann·E. W. N. Glover·G. Heinrich·H. Stenzel
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Abstract

We report on the calculation of NNLO corrections to the 3-jet cross section and related event shape distributions in electron-positron annihilation. The corrections are sizable for all variables, however the magnitude of the corrections 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 normalization of the event shape distributions in the region where the perturbative result is expected to hold. A new extraction of $α_{s}$ using the event shape variables up to NNLO yields a considerably better consistency between the observables indicating a stabilization of the perturbative corrections at this order.

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G. Dissertori, A. Gehrmann-De Ridder, T. Gehrmann, E. W. N. Glover, G. Heinrich, H. Stenzel. 2008-06-27. e^+ e^- -> 3 jets and event shapes at NNLO. https://doi.org/10.1016/j.nuclphysbps.2008.09.072

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