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Hard Processes on Nuclear Targets in QCD

N. Armesto·C. Pajares·C. A. Salgado·Yu. M. Shabelski
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Abstract

We calculate the A-dependence of open charm and beauty as well as Drell-Yan pair production cross sections on nuclear targets taking into account the difference of quark and gluon distributions in free and bound nucleons. The results are presented for both proton-nucleus and nucleus-nucleus collisions. For the case of heavy flavour production at comparatively low energies, if $σ\sim A^α$, the values of $α$ are slightly higher than unity. With increasing energy $α$ decreases in all cases and becomes smaller than unity. We also show $α$ as a function of Feynman-$x$ of the produced $Q\overline{Q}$ or $l^+l^-$ pair and obtain that it decreases significantly in the beam fragmentation region. The sensitivity of our results to the used set of parton distributions is also discussed.

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N. Armesto, C. Pajares, C. A. Salgado, Yu. M. Shabelski. 1996-09-12. Hard Processes on Nuclear Targets in QCD. https://arxiv.org/abs/hep-ph/9609296

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