Quarkonium measurements in nucleus--nucleus collisions with ALICE

Quarkonia, i.e. bound states of bb‾ and cc‾ quarks, are powerful observables to study the properties of nuclear matter under extreme conditions. The formation of a Quark-Gluon Plasma (QGP), which is predicted by lattice QCD calculations at high temperatures as reached at the LHC energies, has a strong influence on the production and behavior of quarkonia. The latest ALICE results on bottomonium and charmonium production in nucleus−nucleus collisions are presented. This includes measurements of the ϒ(1S) and ϒ(2S) nuclear modification factor ( R AA ) at forward rapidity and the J/ψ R AA and ν2 as a function of centrality, p T and rapidity in Pb–Pb collisions at sNN=5.02TeV . Also, first results from J/ψ measurements in Xe–Xe collisions at sNN=5.44TeV are presented. Further on, the experimental results are compared to various calculations from theoretical models.