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Midrapidity production of π ± , K ± , and (p)p measured by the ALICE experiment at the CERN Large Hadron Collider, in Pb-Pb and inelastic pp collisions at √ s NN = 5.02 TeV, is presented. The invariant yields are measured over a wide transverse momentum (p T) range from hundreds of MeV/c up to 20 GeV/c. The results in Pb-Pb collisions are presented as a function of the collision centrality, in the range 0-90%. The comparison of the p T-integrated particle ratios, i.e., proton-to-pion (p/π) and kaon-to-pion (K/π) ratios, with similar measurements in Pb-Pb collisions at √ s NN = 2.76 TeV show no significant energy dependence. Blast-wave fits of the p T spectra indicate that in the most central collisions radial flow is slightly larger at 5.02 TeV with respect to 2.76 TeV. Particle ratios (p/π , K/π) as a function of p T show pronounced maxima at p T ≈ 3 GeV/c in central Pb-Pb collisions. At high p T , particle ratios at 5.02 TeV are similar to those measured in pp collisions at the same energy and in Pb-Pb collisions at √ s NN = 2.76 TeV. Using the pp reference spectra measured at the same collision energy of 5.02 TeV, the nuclear modification factors for the different particle species are derived. Within uncertainties, the nuclear modification factor is particle species independent for high p T and compatible with measurements at √ s NN = 2.76 TeV. The results are compared to state-of-the-art model calculations, which are found to describe the observed trends satisfactorily.

We report measurements of the production of prompt D 0 , D + , D * + and D + s mesons in Pb-Pb collisions at the centre-of-mass energy per nucleon-nucleon pair √ s NN = 5.02 TeV, in the centrality classes 0-10%, 30-50% and 60-80%. The D-meson production yields are measured at mid-rapidity (|y| < 0.5) as a function of transverse momentum (p T). The p T intervals covered in central collisions are: 1 < p T < 50 GeV/c for D 0 , 2 < p T < 50 GeV/c for D + , 3 < p T < 50 GeV/c for D * + , and 4 < p T < 16 GeV/c for D + s mesons. The nuclear modification factors (R AA) for non-strange D mesons (D 0 , D + , D * +) show minimum values of about 0.2 for p T = 6-10 GeV/c in the most central collisions and are compatible within uncertainties with those measured at √ s NN = 2.76 TeV. For D + s mesons, the values of R AA are larger than those of non-strange D mesons, but compatible within uncertainties. In central collisions the average R AA of non-strange D mesons is compatible with that of charged particles for p T > 8 GeV/c, while it is larger at lower p T. The nuclear modification factors for strange and non-strange D mesons are also compared to theoretical models with different implementations of in-medium energy loss.

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We show that the experimental data of p T spectra of identified hadrons released recently by ALICE collaboration for p-Pb collisions at √ s NN = 5.02 TeV exhibit a distinct universal behavior -the quark number scaling.We further show that the scaling is a direct consequence of quark (re-)combination mechanism of hadronization and can be regarded as a strong indication of the existence of the underlying source with constituent quark degree of freedom for the production of hadrons in p-Pb collisions at such high energies. We make also predictions for production of other hadrons.