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Event Shapes and Power Correction Results from HERA

G. J. McCance
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Abstract

Inclusive event shape variables have been measured in the Breit Frame for neutral current deep-inelastic positron-proton scattering using the H1 and ZEUS detectors at HERA. The variables thrust, jet broadening, C-parameter, jet mass and two kinds of differential two-jet rate have been studied in the kinematic range 7 < Q < 100 GeV. The Q dependence of the shape variables have been compared with QCD applying power corrections proportional to 1/Q^p to account for hadronisation effects. The concept of power corrections is tested by fitting the strong coupling constant alpha_s and a non-perturbative parameter alpha(p-1)_bar.

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G. J. McCance. 2000-08-04. Event Shapes and Power Correction Results from HERA. https://arxiv.org/abs/hep-ex/0008009

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