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arXiv · 2311.12768

Subleading power corrections for event shape variables in $e^+ e^-$ annihilation

Luca Buonocore·Massimiliano Grazzini·Flavio Guadagni·Luca Rottoli
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Abstract

We consider subleading power corrections to event shape variables in $e^+e^-$ collisions at the first order in the QCD coupling $\alpha_s$. We start from the jettiness variable $\tau_2$ and the $y_{23}$ resolution variable for the $k_T$ jet clustering algorithm and we analytically compute the corresponding cumulative cross section. We investigate the origin of the different power suppressed contributions in the two-jet limit and trace it back to their different coverage of the phase space. We extend our analysis to the case of thrust and of the $C$-parameter, and we finally discuss a class of observables that depend on a continuous parameter giving different weight to central and forward emissions and we evaluate the corresponding subleading power corrections.

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Luca Buonocore, Massimiliano Grazzini, Flavio Guadagni, Luca Rottoli. 2023-11-21. Subleading power corrections for event shape variables in $e^+ e^-$ annihilation. https://doi.org/10.1140/epjc%2Fs10052-024-12788-5

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