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arXiv · hep-ph/0608326

Two-loop electroweak next-to-leading logarithmic corrections to massless fermionic processes

Abstract

We consider two-loop leading and next-to-leading logarithmic virtual corrections to arbitrary processes with external massless fermions in the electroweak Standard Model at energies well above the electroweak scale. Using the sector-decomposition method and alternatively the strategy of regions we calculate the mass singularities that arise as logarithms of Q^2/MW^2, where Q is the energy scale of the considered process, and 1/εpoles in D=4-2εdimensions, to one- and two-loop next-to-leading logarithmic accuracy. The derivations are performed within the complete electroweak theory with spontaneous symmetry breaking. Our results indicate a close analogy between the form of two-loop electroweak logarithmic corrections and the singular structure of scattering amplitudes in massless QCD. We find agreement with the resummation prescriptions that have been proposed in the literature based on a symmetric SU(2) \times U(1) theory matched with QED at the electroweak scale and provide new next-to-leading contributions proportional to ln(MZ^2/MW^2).

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BibTeXRIS

A. Denner, B. Jantzen, S. Pozzorini. 2006-11-09. Two-loop electroweak next-to-leading logarithmic corrections to massless fermionic processes. https://doi.org/10.1016/j.nuclphysb.2006.10.014

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