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Intrinsic parton transverse momentum in next-to-leading-order pion production

G. Papp·G. G. Barnafoldi·P. Levai·G. Fai
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Abstract

We study pion production in proton-proton collisions within a pQCD-improved parton model in next-to-leading order augmented by intrinsic transverse momentum ($k_\perp$) of the partons. We find the introduction of $k_\perp$ necessary to reproduce the experimental data in the CERN SPS to RHIC energy range. We study the influence of intrinsic $k_\perp$ on the so-called $K$ factor, the ratio of the NLO cross section to the Born term. A strong $p_T$ dependence is seen, especially in the 3-6 GeV transverse momentum region of the outgoing pion, where nuclear effects (e.g. the Cronin effect) play an important role.

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G. Papp, G. G. Barnafoldi, P. Levai, G. Fai. 2003-07-15. Intrinsic parton transverse momentum in next-to-leading-order pion production. https://arxiv.org/abs/hep-ph/0212249

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