ar X iv : h ep - p h / 04 06 33 8 v 1 3 0 Ju n 20 04
نویسندگان
چکیده
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)− s̄(x) in the nucleon’s sea.
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