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Gluon recombination in high parton density QCD: inclusive pion production

Yang Li·Kirill Tuchin
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Abstract

We argue that the collinear factorization of the fragmentation functions in high energy hadron and nuclei collisions breaks down at transverse momenta kT < Qs/g due to high parton densities in the colliding hadrons and/or nuclei. We calculate, at next-to-leading order in projectile parton density and to all orders in target parton density, the double-inclusive cross section for production of a pair of gluons in the scalar J^(PC)=0^(++) channel. Using the low energy theorems of QCD we find the inclusive cross section for pi-meson production.

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Yang Li, Kirill Tuchin. 2007-02-20. Gluon recombination in high parton density QCD: inclusive pion production. https://doi.org/10.1103/physrevd.75.074022

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