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arXiv · 1408.4659

LHC data challenges the contemporary parton-to-hadron fragmentation functions

David d'Enterria·Kari J. Eskola·Ilkka Helenius·Hannu Paukkunen
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Abstract

We discuss the inclusive high-pT charged-particle production in proton-proton collisions at the LHC. The experimental data are compared to the NLO perturbative QCD calculations employing various sets of parton-to-hadron fragmentation functions. Most of the theoretical predictions are found to disastrously overpredict the measured cross sections, even if the scale variations and PDF errors are accounted for. The problem appears to arise from the presently too hard gluon-to-hadron fragmentation functions.

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David d'Enterria, Kari J. Eskola, Ilkka Helenius, Hannu Paukkunen. 2014-08-20. LHC data challenges the contemporary parton-to-hadron fragmentation functions. https://arxiv.org/abs/1408.4659

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