2022/08/21 by Dusan Zigic, Jussi Auvinen, Zigic, Dusan +7 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2208.09886
openalex publication_date 2022/08/21 · openalex created_date 2022/08/24 · openalex updated_date 2026/07/28
QGP tomography aims to constrain the parameters characterizing the properties and evolution of Quark-Gluon Plasma (QGP) formed in heavy-ion collisions, by exploiting low and high-p_⊥ theory and data. Higher-order harmonics vn (n>2) are an important -- but seldom explored -- part of this approach. However, to take full advantage of them, several issues have to be addressed: i) consistency of different methods for calculating vn, ii) importance of event-by-event fluctuations to high-p_⊥ RAA and v2 predictions, iii) sensitivity of higher harmonics to the initial state of fluid-dynamical evolution. We obtain that i) several methods for calculating harmonics are compatible with each other, ii) event-by-event calculations are important in mid-central collisions, and iii) various initializations of the evolution of the medium lead to quantitatively and qualitatively different predictions, likely to be distinguished by future measurements. We also find that the present high-p_⊥ v4 data cannot be reproduced using initial states for fluid-dynamical evolution given by state-of-the-art models. We call this discrepancy high-p_⊥ v4 puzzle at the LHC.