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Subtraction terms at NNLO

Stefan Weinzierl
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Abstract

Perturbative calculations at next-to-next-to-leading order for multi-particle final states require a method to cancel infrared singularities. I discuss the subtraction method at NNLO. As a concrete example I consider the leading-colour contributions to e+ e- --> 2 jets. This is the simplest example which exhibits all essential features. For this example, explicit subtraction terms are given, which approximate the four-parton and three-parton final states in all double and single unresolved limits, such that the subtracted matrix elements can be integrated numerically.

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Stefan Weinzierl. 2003-02-20. Subtraction terms at NNLO. https://doi.org/10.1088/1126-6708%2F2003%2F03%2F062

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