Systematic study of flow vector fluctuations in √𝑠𝑁𝑁=5.02 TeV Pb-Pb collisions

Scientific paper - Original scientific paper

• Author: S. Acharya
• Author: ...
• Author: Sven Gotovac
• Author: ...
• Author: David Karatović
• Author: ...
• Author: Nino Kovačić
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: N. Zurlo
• Collaboration: ALICE Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Measurements of the 𝑝T-dependent flow vector fluctuations in Pb–Pb collisions at √𝑠NN=5.02TeV using azimuthal correlations with the ALICE experiment at the Large Hadron Collider are presented. A four-particle correlation approach [ALICE Collaboration, Phys. Rev. C 107, L051901 (2023)] is used to quantify the effects of flow angle and magnitude fluctuations separately. This paper extends previous studies to additional centrality intervals and provides measurements of the 𝑝T-dependent flow vector fluctuations at √𝑠NN=5.02TeV with two-particle correlations. Significant 𝑝T-dependent fluctuations of the ⃗𝑉2 flow vector in Pb–Pb collisions are found across different centrality ranges, with the largest fluctuations of up to ∼15% being present in the 5% most central collisions. In parallel, no evidence of significant 𝑝T-dependent fluctuations of ⃗𝑉3 or ⃗𝑉4 is found. Additionally, evidence of flow angle and magnitude fluctuations is observed with more than 5⁢𝜎 significance in central collisions. These observations in Pb–Pb collisions indicate where the classical picture of hydrodynamic modeling with a common symmetry plane breaks down. This has implications for hard probes at high 𝑝T, which might be biased by 𝑝T-dependent flow angle fluctuations of at least 23% in central collisions. Given the presented results, existing theoretical models should be reexamined to improve our understanding of initial conditions, quark–gluon plasma properties, and the dynamic evolution of the created system.

• Keywords (english): flow vector fluctuations; Pb-Pb collisions
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review C
• Numbering: vol. 109, no. 6, 065202
• p-ISSN: 2469-9985
• e-ISSN: 2469-9993
• DOI: https://doi.org/10.1103/PhysRevC.109.065202
• URN:NBN: urn:nbn:hr:217:000367
• Publication: 2024
• Document URL: https://link.aps.org/doi/10.1103/PhysRevC.109.065202
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2024 CERN, for the ALICE Collaboration. 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. Open access publication funded by CERN. Received 4 April 2024; accepted 10 May 2024; published 13 June 2024.
• Created on: 2024-09-13 12:42:57