J/psi production in pp and heavy-ion collisions at ATLAS

The inclusive J/psi production cross-section and fraction of J/Psi mesons produced in B-hadron decays are measured in proton-proton collisions at \sqrt{s}=7 TeV with the ATLAS detector at the LHC, as a function of the transverse momentum and rapidity of the J/Psi, using 2.3~pb-1 of the integrated luminosity. The differential production cross-sections of prompt and non-prompt J/\psi are separately determined and are compared to Colour Singlet NNLO^*, Colour Evaporation Model, and FONLL predictions. In this proceeding, a centrality-dependent suppression in the yield of J/Psi mesons decaying to \mu^+\mu^- pairs in lead-lead run at psNN=2.76 TeV is discussed along with an observation of the Z boson production.