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Precision calculations for gamma gamma --> WW --> 4fermions(+gamma)

A. Bredenstein·S. Dittmaier·M. Roth
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Abstract

The O(alpha) electroweak radiative corrections to gamma gamma --> WW --> 4f within the electroweak Standard Model are calculated in double-pole approximation (DPA). Virtual corrections are treated in DPA, and real-photonic corrections are based on complete lowest-order matrix elements for gamma gamma --> 4f+gamma. The radiative corrections are implemented in a Monte Carlo generator called COFFERgammagamma, which optionally includes anomalous triple and quartic gauge-boson couplings in addition and performs a convolution over realistic spectra of the photon beams. A brief survey of numerical results comprises O(alpha) corrections to integrated cross sections as well as to angular and invariant-mass distributions.

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A. Bredenstein, S. Dittmaier, M. Roth. 2005-06-03. Precision calculations for gamma gamma --> WW --> 4fermions(+gamma). https://arxiv.org/abs/hep-ph/0506024

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