Study of flow harmonic ratios in Au+Au collisions at √sNN = 200 GeV and comparison with AMPT simulations*

High-energy heavy-ion collisions can create a deconfined nuclear matter, the quark-gluon plasma (QGP), under extreme conditions akin to those of the early universe. The Fourier coefficients (vn) of the final-state particle emission characterize the collective motions of the QGP. These collective motions can be described by relativistic hydrodynamics, whereby the QGP droplets behave like a strongly interacting fluid. In the hydrodynamic framework, vn is a power-law function of transverse momentum (pT), which predicts the ratios of v31/3/v21/2 and v41/4/v21/2 to be independent of pT [1]. We analyze the published vn data of Au+Au collision at √sNN = 200 GeV provided by the STAR experiment and examine these ratios for pions, kaons, and protons separately in fine centrality intervals. We find constant flow harmonic ratios around unity with negligible dependence on pT across a broad centrality range for all particle species, supporting the hydrodynamic hypothesis. Furthermore, we employ a multiphase transport model (AMPT) to simulate Au+Au collisions and to compare them with the STAR data. The physics implication will be discussed.

[1] D. Adamová et al., arXiv:2402.10895 [nucl-x].