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arXiv · 1309.4393

The two-loop soft current in dimensional regularization

Claude Duhr·Thomas Gehrmann
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Abstract

The soft current describes the factorization behavior of quantum chromodynamics (QCD) scattering amplitudes in the limit of vanishing energy of one of the external partons. It is process-independent and can be expanded in a perturbative series in the coupling constant. To all orders in the dimensional regularization parameter, we compute the two-loop correction to the soft current for processes involving two hard partons.

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Claude Duhr, Thomas Gehrmann. 2013-09-17. The two-loop soft current in dimensional regularization. https://doi.org/10.1016/j.physletb.2013.10.063

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