J/ψ + Z production at the LHC

We briefly review recent results which we have obtained in the study of J/ψ + Z production at the LHC. Considering our NLO computation in the Colour Evaporation Model (CEM) as an upper theory limit for the single-parton-scattering contributions, we claim that the existing data set from ATLAS points at a dominant double-partonscattering contribution with an effective cross section smaller than that for jet-related observables. As a side product of our analysis, we have computed, for the first time, the one-loop QCD corrections to the J/ψ PT-differential cross section in the CEM