These proceedings summarise recent measurements of angular correlations between the Ξ baryon and identified hadrons in pp collisions at √
S
= 13 TeV using the ALICE detector. The results are compared ...with both string-based (PYTHIA8 with extensions) and core-corona (EPOS-LHC) models, to improve our understanding of strangeness and baryon production in small systems. The results favour baryon production through string junctions over diquark breaking, but the PYTHIA models fail at describing the relatively wide Ξ—strangeness jet peak, indicating stronger diffusion of strange quarks in data. On the other hand, EPOS-LHC is missing local conservation of quantum numbers, making it difficult to draw any conclusion about the core-corona model.
These proceedings summarise the first measurements of anisotropic flow coefficients v n , 2 ≤ n ≤ 4 , for inclusive charged particles at mid-rapidity in Xe–Xe collisions at s NN = 5 . 44 TeV . The ...results are compared with those from Pb–Pb collisions at s NN = 5 . 02 TeV , in order to test the initial state (IS) models and transport properties. The resulting differences in v 2 and v 3 between the two systems are consistent with two different hydrodynamical models. Moreover, it is expected that the ratios between v n and their corresponding eccentricities for n = 2 , 3 scale with transverse density. This is observed for some IS models, except for some deviations in central collisions. These results assist in constraining the initial state as well as the hydrodynamical propagation of the system.
The global polarization of the Λ and Λ hyperons is measured for Pb-Pb collisions at sNN=2.76 and 5.02 TeV recorded with the ALICE at the Large Hadron Collider (LHC). The results are reported ...differentially as a function of collision centrality and hyperon's transverse momentum (pT) for the range of centrality 5-50%, 0.5<pT<5 GeV/c, and rapidity |y|<0.5. The hyperon global polarization averaged for Pb-Pb collisions at sNN=2.76 and 5.02 TeV is found to be consistent with zero, (PH)(%)≈0.01±0.06(stat.)±0.03(syst.) in the collision centrality range 15-50%, where the largest signal is expected. The results are compatible with expectations based on an extrapolation from measurements at lower collision energies at the Relativistic Heavy Ion Collider, hydrodynamical model calculations, and empirical estimates based on collision energy dependence of directed flow, all of which predict the global polarization values at LHC energies of the order of 0.01%.
First experimental results are presented on event-by-event net-proton fluctuation measurements in Pb–Pb collisions at sNN=2.76 TeV, recorded by the ALICE detector at the CERN LHC. The ALICE detector ...is well suited for such studies due to its excellent particle identification capabilities and large acceptance, which is crucial for fluctuation analysis. The studies are focussed on second order cumulants, but the analysis technique used is more general and will be applied, in the near future, also to higher order cumulants.
These proceedings summarise recent measurements of angular correlations
between the $\Xi$ baryon and identified hadrons in pp collisions at
$\sqrt{s}=13\,\mathrm{TeV}$ using the ALICE detector. The ...results are compared
with both string-based (PYTHIA8 with extensions) and core-corona (EPOS-LHC)
models, to improve our understanding of strangeness and baryon production in
small systems. The results favour baryon production through string junctions
over diquark breaking, but the PYTHIA models fail at describing the relatively
wide $\Xi-$strangeness jet peak, indicating stronger diffusion of strange
quarks in data. On the other hand, EPOS-LHC is missing local conservation of
quantum numbers, making it difficult to draw any conclusion about the
core-corona model.
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