A1 Journal article (refereed)
Constraining the Chiral Magnetic Effect with charge-dependent azimuthal correlations in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV (2020)

ALICE collaboration. (2020). Constraining the Chiral Magnetic Effect with charge-dependent azimuthal correlations in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV. Journal of High Energy Physics, 2020(9), Article 160. https://doi.org/10.1007/JHEP09(2020)160

JYU authors or editors

Publication details

All authors or editors: ALICE collaboration

Journal or series: Journal of High Energy Physics

ISSN: 1126-6708

eISSN: 1029-8479

Publication year: 2020

Volume: 2020

Issue number: 9

Article number: 160

Publisher: Springer

Publication country: Germany

Publication language: English

DOI: https://doi.org/10.1007/JHEP09(2020)160

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/72025

Web address of parallel published publication (pre-print): https://arxiv.org/abs/2005.14640

Abstract

Systematic studies of charge-dependent two- and three-particle correlations in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV used to probe the Chiral Magnetic Effect (CME) are presented. These measurements are performed for charged particles in the pseudorapidity (η) and transverse momentum (pT) ranges |η| < 0.8 and 0.2 < pT < 5 GeV/c. A significant charge-dependent signal that becomes more pronounced for peripheral collisions is reported for the CME-sensitive correlators γ1, 1 = 〈cos(φα + φβ − 2Ψ2)〉 and γ1, − 3 = 〈cos(φα − 3φβ + 2Ψ2)〉. The results are used to estimate the contribution of background effects, associated with local charge conservation coupled to anisotropic flow modulations, to measurements of the CME. A blast-wave parametrisation that incorporates local charge conservation tuned to reproduce the centrality dependent background effects is not able to fully describe the measured γ1,1. Finally, the charge and centrality dependence of mixed-harmonics three-particle correlations, of the form γ1, 2 = 〈cos(φα + 2φβ − 3Ψ3)〉, which are insensitive to the CME signal, verify again that background contributions dominate the measurement of γ1,1.

Keywords: particle physics

Free keywords: Hadron-Hadron scattering (experiments)

Contributing organizations

Ministry reporting: Yes

VIRTA submission year: 2020

JUFO rating: 2