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arXiv · 2007.15360

Four lepton production and the accuracy of QED FSR

Christian Gütschow·Marek Schönherr
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Abstract

We scrutinise the ability of the primary QED final-state resummation tools, combined with electroweak virtual corrections, to reproduce the exact next-to-leading order electroweak calculation in the four-charged-lepton final state. We further examine the dependence of the findings on the lepton-photon dressing-cone size as well as the resonance identification strategy. Overall we find excellent agreement with the fixed-order result, but partial differences not directly connected with resummation-induced higher-order effects at the few-percent level are observed in some cases, which are relevant for precision measurements.

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Christian Gütschow, Marek Schönherr. 2020-07-30. Four lepton production and the accuracy of QED FSR. https://doi.org/10.1140/epjc%2Fs10052-020-08816-9

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