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arXiv · hep-ph/0011222

One-loop Singular Behaviour of QCD and SUSY QCD Amplitudes with Massive Partons

Stefano Catani·Stefan Dittmaier·Zoltan Trocsanyi
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Abstract

We discuss the structure of infrared and ultraviolet singularities in on-shell QCD and supersymmetric QCD amplitudes at one-loop order. Previous results, valid for massless partons, are extended to the case of massive partons. Using dimensional regularization, we present a general factorization formula that controls both the singular epsilon-poles and the logarithmic contributions that become singular for vanishing masses. We introduce generalized Altarelli--Parisi splitting functions and discuss their relations with the singular terms in the amplitudes. The dependence on the regularization scheme is also considered.

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Stefano Catani, Stefan Dittmaier, Zoltan Trocsanyi. 2000-11-27. One-loop Singular Behaviour of QCD and SUSY QCD Amplitudes with Massive Partons. https://doi.org/10.1016/s0370-2693(01)00065-x

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