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Title: Higher-order symmetry plane correlations in Pb-Pb collisions at sNN=5.02TeV
The correlations between event-by-event fluctuations of symmetry planes are measured in Pb-Pb collisions at a center-of-mass energy per nucleon pair sNN =5.02TeV recorded by the ALICE detector at the Large Hadron Collider. This analysis is conducted using the Gaussian estimator technique, which is insensitive to biases from correlations between different flow amplitudes. The study presents, for the first time, the centrality dependence of correlations involving up to five different symmetry planes. The correlation strength varies depending on the harmonic order of the symmetry plane and the collision centrality. Comparisons with measurements from lower energies indicate no significant differences within uncertainties. Additionally, the results are compared with hydrodynamic model calculations. Although the model predictions provide a qualitative explanation of the experimental results, they overestimate the data for some observables. This is particularly true for correlators that are sensitive to the nonlinear response of the medium to initial-state anisotropies in the collision system. As these new correlators provide unique information—independent of flow amplitudes—their usage in future model developments can further constrain the properties of the strongly interacting matter created in ultrarelativistic heavy-ion collisions.  more » « less
Award ID(s):
2012154 2208883
PAR ID:
10627347
Author(s) / Creator(s):
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Corporate Creator(s):
Publisher / Repository:
Physical Review Journals
Date Published:
Journal Name:
Physical Review C
Volume:
111
Issue:
6
ISSN:
2469-9985
Page Range / eLocation ID:
4913
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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