Abstract
The correlations between flow harmonics for , 3, and 4 and mean transverse momentum in and collisions at and 5.02 TeV, respectively, are measured using charged particles with the ATLAS detector. The correlations are potentially sensitive to the shape and size of the initial geometry, nuclear deformation, and initial momentum anisotropy. The effects from nonflow and centrality fluctuations are minimized, respectively, via a subevent cumulant method and an event-activity selection based on particle production at very forward rapidity. The correlations show strong dependencies on centrality, harmonic number , , and pseudorapidity range. Current models qualitatively describe the overall centrality- and system-dependent trends but fail to quantitatively reproduce all features of the data. In central collisions, where models generally show good agreement, the correlations are sensitive to the triaxiality of the quadruple deformation. Comparison of the model with the and data confirms that the nucleus is a highly deformed triaxial ellipsoid that has neither a prolate nor oblate shape. This provides strong evidence for a triaxial deformation of the nucleus from high-energy heavy-ion collisions.
2 More- Received 3 May 2022
- Accepted 29 August 2022
DOI:https://doi.org/10.1103/PhysRevC.107.054910
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
©2023 CERN, for the ATLAS Collaboration