Anisotropic flow in high baryon density region

作者：Shao-Wei Lan^*; Shu-Su Shi

来源：Nuclear Science and Techniques, 2022, 33(3): 21.

DOI：10.1007/s41365-022-01006-0

• Heavy-ion collisions
• QCD phase diagram
• UrQMD
• Collective flow
• Mean-field potential

Collective flow is a powerful tool used to analyze the properties of a medium created during high-energy nuclear collisions. Here, we report a systematic study of the first two Fourier coefficients nu(1) and nu(2) of the proton and pi(+) from Au+Au collisions in the energy range root S-NN = 2.11-4.9 GeV within the framework of a hadronic transport model (UrQMD). Recent results from the STAR experiment were used to test the model calculations. A mean-field mode with strong repulsive interaction is needed to reproduce the 10-40% data at 3 GeV. This implies that hadronic interactions play an important role in the collective flow development in the high baryon density region. The mean values of the freeze-out time for protons and pi(+) are shifted earlier owing to the additional repulsive interactions. We predict the energy dependence of the mean values of the transverse momentum < P-T >, nu(1), and nu(2) for both protons and pi(+) from the Au+Au collisions.