Quarkonium production in ALICE at the LHC

TL;DR

This paper reviews ALICE's measurements of quarkonium production in various LHC collision systems, providing insights into QGP properties and cold nuclear matter effects through new experimental data and analysis.

Contribution

It presents new measurements of quarkonium production in p-Pb and Pb-Pb collisions, including p_T dependence and B hadron contributions, enhancing understanding of QGP and cold nuclear matter effects.

Findings

Inclusive J/psi, psi(2S), and Upsilon production measured in p-Pb collisions.

p_T dependence of inclusive J/psi in Pb-Pb collisions analyzed.

Estimation of cold nuclear matter effects extrapolated from p-Pb data.

Abstract

In heavy-ion collisions at the LHC, the ALICE Collaboration is studying Quantum Chromodynamics (QCD) matter at very high energy density where the formation of a Quark Gluon Plasma (QGP) is expected. Quarkonium production is an important probe to characterize the QGP properties. High precision data in pp collisions provide the baseline of Pb-Pb measurements and p-Pb collisions serve to quantify the amount of initial and/or final state effects, related to cold nuclear matter, that are largely unknown at the LHC energy. Since 2010, the LHC provided Pb-Pb collisions at sqrt{s_{NN}} = 2.76 TeV, pp collisions at various energies and in 2013 p-Pb collisions at sqrt{s_{NN}} = 5.02 TeV. In ALICE, quarkonia can be reconstructed at forward rapidity in the dimuon channel and at mid-rapidity in the dielectron channel, and, for both channels, down to zero transverse momentum. New measurements on inclusive production of J/psi, psi (2S) and Upsilon performed in p-Pb collisions and on the p_T dependence of inclusive J/psi in Pb-Pb collisions are presented. The contribution of J/psi from B hadrons to the inclusive production in Pb-Pb is also discussed. Finally, an estimation of the cold nuclear matter effect in Pb-Pb, extrapolated from p-Pb measurements, is given.