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arXiv · 1101.5295

Cold Nuclear Matter Effects on jpsi Production with Extrinsic pT at $\sqrt{s_{NN}}=5.5\mathrm{~TeV}$ at the LHC

E. G. Ferreiro·F. Fleuret·J. P. Lansberg·N. Matagne·A. Rakotozafindrabe
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Abstract

Taking into account the gluon shadowing and the $J/ψ$ nuclear absorption, we evaluate the Cold Nuclear Matter (CNM) effects on $J/ψ$ production in $p$Pb and PbPb collisions at the design LHC energy for PbPb collisions, $\sqrt{s_{NN}}=5.5$ TeV. In view of the good agreement between the yield prediction using the LO CSM and the ALICE data at 7 TeV, we employ the latter model to use a complete description of the kinematics of the underlying $2 \rightarrow 2$ partonic process, namely $g + g \rightarrow J/ψ+ g$. We observe a large $J/ψ$ suppression in $p$Pb and PbPb collisions due to the strong shadowing of the gluon distribution in the lead ion at the corresponding gluon momentum fractions. This suppression from CNM effects has a strong rapidity dependence which may compensate, partially or completely, that of of the predicted charm recombination in PbPb collisions.

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E. G. Ferreiro, F. Fleuret, J. P. Lansberg, N. Matagne, A. Rakotozafindrabe. 2011-02-08. Cold Nuclear Matter Effects on jpsi Production with Extrinsic pT at $\sqrt{s_{NN}}=5.5\mathrm{~TeV}$ at the LHC. https://arxiv.org/abs/1101.5295

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