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Planar two-loop master integrals for massive Bhabha scattering: N_f=1 and N_f=2

Stefano Actis·Michal Czakon·Janusz Gluza·Tord Riemann
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Abstract

Recent developments in the computation of two-loop master integrals for massive Bhabha scattering are briefly reviewed. We apply a method based on expansions of exact Mellin-Barnes representations and evaluate all planar four-point master integrals in the approximation of small electron mass at fixed scattering angle for the one-flavor case. The same technique is employed to derive and evaluate also all two-loop masters generated by additional fermion flavors. The approximation is sufficient for the determination of QED two-loop corrections for Bhabha scattering in the kinematics planned to be used for the luminosity determination at the ILC.

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Stefano Actis, Michal Czakon, Janusz Gluza, Tord Riemann. 2007-07-26. Planar two-loop master integrals for massive Bhabha scattering: N_f=1 and N_f=2. https://doi.org/10.1016/j.nuclphysbps.2006.09.034

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