Measurements of anisotropic flow coefficients with two-and multi-particle cumulants for inclusive charged particles in Pb-Pb collisions at √ s NN = 5.02 and 2.76 TeV are reported in the pseudorapidity range |η| < 0.8 and transverse momentum 0.2 < p T < 50 GeV/c. The full data sample collected by the ALICE detector in 2015 (2010), corresponding to an integrated luminosity of 12.7 (2.0) µb −1 in the centrality range 0-80%, is analysed. Flow coefficients up to the sixth flow harmonic (v 6 ) are reported and a detailed comparison among results at the two energies is carried out. The p T dependence of anisotropic flow coefficients and its evolution with respect to centrality and harmonic number n are investigated. An approximate power-law scaling of the form v n (p T ) ∼ p n/3 T is observed for all flow harmonics at low p T (0.2 < p T < 3 GeV/c). At the same time, the ratios v n /v n/m m are observed to be essentially independent of p T for most centralities up to about p T = 10 GeV/c. Analysing the differences among higher-order cumulants of elliptic flow (v 2 ), which have different sensitivities to flow fluctuations, a measurement of the standardised skewness of the event-by-event v 2 distribution P (v 2 ) is reported and constraints on its higher moments are provided. The Elliptic Power distribution is used to parametrise P (v 2 ), extracting its parameters from fits to cumulants. The measurements are compared to different model predictions in order to discriminate among initial-state models and to constrain the temperature dependence of the shear viscosity to entropy-density ratio.
The production of J/ψ is measured at midrapidity (|y| < 0.9) in proton-proton collisions at $$ \sqrt{s} $$ s = 5.02 and 13 TeV, through the dielectron decay channel, using the ALICE detector at the Large Hadron Collider. The data sets used for the analyses correspond to integrated luminosities of $$ \mathcal{L} $$ L int = 19.4 ± 0.4 nb−1 and $$ \mathcal{L} $$ L int = 32.2 ± 0.5 nb−1 at $$ \sqrt{s} $$ s = 5.02 and 13 TeV, respectively. The fraction of non-prompt J/ψ mesons, i.e. those originating from the decay of beauty hadrons, is measured down to a transverse momentum pT = 2 GeV/c (1 GeV/c) at $$ \sqrt{s} $$ s = 5.02 TeV (13 TeV). The pT and rapidity (y) differential cross sections, as well as the corresponding values integrated over pT and y, are carried out separately for prompt and non-prompt J/ψ mesons. The results are compared with measurements from other experiments and theoretical calculations based on quantum chromodynamics (QCD). The shapes of the pT and y distributions of beauty quarks predicted by state-of-the-art perturbative QCD models are used to extrapolate an estimate of the $$ \mathrm{b}\overline{\mathrm{b}} $$ b b ¯ pair cross section at midrapidity and in the total phase space. The total $$ \mathrm{b}\overline{\mathrm{b}} $$ b b ¯ cross sections are found to be $$ {\sigma}_{\mathrm{b}\overline{\mathrm{b}}} $$ σ b b ¯ = 541 ± 45 (stat.) ± 69 $$ {\left(\mathrm{syst}.\right)}_{-12}^{+10} $$ syst . − 12 + 10 (extr.) μb and $$ {\sigma}_{\mathrm{b}\overline{\mathrm{b}}} $$ σ b b ¯ = 218±37 (stat.)±31 $$ {\left(\mathrm{syst}.\right)}_{-9.1}^{+8.2} $$ syst . − 9.1 + 8.2 (extr.) μb at $$ \sqrt{s} $$ s = 13 and 5.02 TeV, respectively. The value obtained from the combination of ALICE and LHCb measurements in pp collisions at $$ \sqrt{s} $$ s = 13 TeV is also provided.
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