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arXiv · hep-ph/0406338

Collinear splitting, parton evolution and the strange-quark asymmetry of the nucleon in NNLO QCD

German Rodrigo·Stefano Catani·Daniel de Florian·Werner Vogelsang
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Abstract

We consider the collinear limit of QCD amplitudes at one-loop order, and their factorization properties directly in colour space. These results apply to the multiple collinear limit of an arbitrary number of QCD partons, and are a basic ingredient in many higher-order computations. In particular, we discuss the triple collinear limit and its relation to flavour asymmetries in the QCD evolution of parton densities at three loops. As a phenomenological consequence of this new effect, and of the fact that the nucleon has non-vanishing quark valence densities, we study the perturbative generation of a strange--antistrange asymmetry $s(x)-\bar{s}(x)$ in the nucleon's sea.

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German Rodrigo, Stefano Catani, Daniel de Florian, Werner Vogelsang. 2004-06-30. Collinear splitting, parton evolution and the strange-quark asymmetry of the nucleon in NNLO QCD. https://doi.org/10.1016/j.nuclphysbps.2004.09.048

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