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arXiv · 1206.6363

On the breaking of collinear factorization in QCD

Jeffrey R. Forshaw·Michael H. Seymour·Andrzej Siodmok
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Abstract

We investigate the breakdown of collinear factorization for non-inclusive observables in hadron-hadron collisions. For pure QCD processes, factorization is violated at the three-loop level and it has a structure identical to that encountered previously in the case of super-leading logarithms. In particular, it is driven by the non-commutation of Coulomb/Glauber gluon exchanges with other soft exchanges. Beyond QCD, factorization may be violated at the two-loop level provided that the hard subprocess contains matrix element contributions with phase differences between different colour topologies.

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Jeffrey R. Forshaw, Michael H. Seymour, Andrzej Siodmok. 2012-06-27. On the breaking of collinear factorization in QCD. https://doi.org/10.1007/jhep11(2012)066

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