A1 Journal article (refereed)
Global polarization of ΛΛ¯ hyperons in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV (2020)

ALICE Collaboration. (2020). Global polarization of ΛΛ¯ hyperons in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV. Physical Review C, 101(4), Article 044611. https://doi.org/10.1103/PhysRevC.101.044611

JYU authors or editors

Publication details

All authors or editorsALICE Collaboration

Journal or seriesPhysical Review C



Publication year2020


Issue number4

Article number044611

PublisherAmerican Physical Society

Publication countryUnited States

Publication languageEnglish


Publication open accessOpenly available

Publication channel open accessPartially open access channel

Publication is parallel published (JYX)https://jyx.jyu.fi/handle/123456789/69056

Web address of parallel published publication (pre-print)https://arxiv.org/abs/1909.01281


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<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%.

Keywordsparticle physics

Contributing organizations

Ministry reportingYes

Reporting Year2020

JUFO rating2

Last updated on 2024-03-04 at 21:35