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arXiv · 0710.5111

Fermionic NNLO contributions to Bhabha scattering

S. Actis·M. Czakon·J. Gluza·T. Riemann
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Abstract

We derive the two-loop corrections to Bhabha scattering from heavy fermions using dispersion relations. The double-box contributions are expressed by three kernel functions. Convoluting the perturbative kernels with fermionic threshold functions or with hadronic data allows to determine numerical results for small electron mass m_e, combined with arbitrary values of the fermion mass m_f in the loop, $m_e^2<<s,t,m_f^2$, or with hadronic insertions. We present numerical results for m_f = m_μ, m_τ, m_{top} at typical small- and large-angle kinematics ranging from 1 GeV to 500 GeV.

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S. Actis, M. Czakon, J. Gluza, T. Riemann. 2007-10-27. Fermionic NNLO contributions to Bhabha scattering. https://arxiv.org/abs/0710.5111

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