We report the measured transverse momentum (p T) spectra of primary charged particles from pp, p-Pb and Pb-Pb collisions at a center-of-mass energy √ s NN = 5.02 TeV in the kinematic range of 0.15 < p T < 50 GeV/c and |η| < 0.8. A significant improvement of systematic uncertainties motivated the reanalysis of data in pp and Pb-Pb collisions at √ s NN = 2.76 TeV, as well as in p-Pb collisions at √ s NN = 5.02 TeV, which is also presented. Spectra from Pb-Pb collisions are presented in nine centrality intervals and are compared to a reference spectrum from pp collisions scaled by the number of binary nucleon-nucleon collisions. For central collisions, the p T spectra are suppressed by more than a factor of 7 around 6-7 GeV/c with a significant reduction in suppression towards higher momenta up to 30 GeV/c. The nuclear modification factor R pPb , constructed from the pp and p-Pb spectra measured at the same collision energy, is consistent with unity above 8 GeV/c. While the spectra in both pp and Pb-Pb collisions are substantially harder at √ s NN = 5.02 TeV compared to 2.76 TeV, the nuclear modification factors show no significant collision energy dependence. The obtained results should provide further constraints on the parton energy loss calculations to determine the transport properties of the hot and dense QCD matter.
The elliptic (v 2 ), triangular (v 3 ), and quadrangular (v 4 ) flow coefficients of π ± , K ± , p + p, Λ + Λ, K 0 S , and the φ-meson are measured in Pb-Pb collisions at √ s NN = 5.02 TeV. Results obtained with the scalar product method are reported for the rapidity range |y| < 0.5 as a function of transverse momentum, p T , at different collision centrality intervals between 0-70%, including ultra-central (0-1%
We present a study of the inclusive chargedparticle transverse momentum (p T) spectra as a function of charged-particle multiplicity density at mid-pseudorapidity, dN ch /dη, in pp collisions at √ s = 5.02 and 13 TeV covering the kinematic range |η| < 0.8 and 0.15 < p T < 20 GeV/c. The results are presented for events with at least one charged particle in |η| < 1 (INEL > 0). The p T spectra are reported for two multiplicity estimators covering different pseudorapidity regions. The p T spectra normalized to that for INEL > 0 show little energy dependence. Moreover, the highp T yields of charged particles increase faster than the charged-particle multiplicity density. The average p T as a function of multiplicity and transverse spherocity is reported for pp collisions at √ s = 13 TeV. For low-(high-) spherocity events, corresponding to jet-like (isotropic) events, the average p T is higher (smaller) than that measured in INEL > 0 pp collisions. Within uncertainties, the functional form of p T (N ch) is not affected by the spherocity selection. While EPOS LHC gives a good description of many features of data, PYTHIA overestimates the average p T in jet-like events.
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.
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