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Separation of soft and collinear infrared limits of QCD squared matrix elements

Zoltan Nagy·Gabor Somogyi·Zoltan Trocsanyi
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Abstract

We present a simple way of separating the overlap between the soft and collinear factorization formulae of QCD squared matrix elements. We check its validity explicitly for single and double unresolved emissions of tree-level processes. The new method makes possible the definition of helicity-dependent subtraction terms for regularizing the real contributions in computing radiative corrections to QCD jet cross sections. This implies application of Monte Carlo helicity summation in computing higher order corrections.

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Zoltan Nagy, Gabor Somogyi, Zoltan Trocsanyi. 2007-02-28. Separation of soft and collinear infrared limits of QCD squared matrix elements. https://arxiv.org/abs/hep-ph/0702273

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