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arXiv · hep-ph/9802439

The Singular Behaviour of QCD Amplitudes at Two-loop Order

Stefano Catani
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Abstract

We discuss the structure of infrared singularities in on-shell QCD amplitudes at two-loop order. We present a general factorization formula that controls all the $\ep$-poles of the dimensionally regularized amplitudes. The dependence on the regularization scheme is considered and the coefficients of the $1/\ep^4, 1/\ep^3$ and $1/\ep^2$ poles are explicitly given in the most general case. The remaining single-pole contributions are also explicitly evaluated in the case of amplitudes with a $q{\bar q}$ pair.

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Stefano Catani. 1998-02-26. The Singular Behaviour of QCD Amplitudes at Two-loop Order. https://doi.org/10.1016/s0370-2693(98)00332-3

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