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arXiv · 0801.2647

Two-loop electroweak Sudakov logarithms for massive fermion scattering

A. Denner·B. Jantzen·S. Pozzorini
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Abstract

We study the asymptotic behaviour of two-loop electroweak corrections at energies Q >> M_W, where logarithms of the type ln(Q/M_W) become dominant. The calculation of the leading and next-to-leading logarithmic terms for massless and massive fermion-scattering processes is summarized. The derivations are performed diagrammatically within the spontaneously broken electroweak theory. We find that the soft and collinear singularities resulting from photons can be factorized into a QED-like term and that, up to logarithms of the Z-W mass ratio, the effects of symmetry breaking cancel. This result supports resummation prescriptions that are based on a symmetric SU(2)xU(1) theory matched with QED at the electroweak scale.

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A. Denner, B. Jantzen, S. Pozzorini. 2008-01-17. Two-loop electroweak Sudakov logarithms for massive fermion scattering. https://doi.org/10.22323/1.048.0002

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