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Four-fermion production at gamma gamma colliders: 2. Radiative corrections in double-pole approximation

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, leading to a classification into factorizable and non-factorizable contributions, and real-photonic corrections are based on complete lowest-order matrix elements for gamma gamma --> 4f + gamma. Soft and collinear singularities appearing in the virtual and real corrections are combined alternatively in two different ways, namely by using the dipole subtraction method or by applying phase-space slicing. 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 detailed survey of numerical results comprises O(alpha) corrections to integrated cross sections as well as to angular, energy, and invariant-mass distributions. Particular attention is paid to the issue of collinear-safety in the observables.

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A. Bredenstein, S. Dittmaier, M. Roth. 2005-06-01. Four-fermion production at gamma gamma colliders: 2. Radiative corrections in double-pole approximation. https://doi.org/10.1140/epjc%2Fs2005-02343-5

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