Beam-energy dependence of correlations between mean transverse momentum and anisotropic flow of charged particles in Au+Au collisions at RHIC

2024/11/18 by The STAR Collaboration
#FOS: Physical sciences #Nuclear Experiment (nucl-ex)

paper · doi:10.48550/arxiv.2411.12101

Abstract

The correlation between the mean transverse momentum, [p_T], and the squared anisotropic flow, v²_n, on an event-by-event basis has been suggested to be influenced by the initial conditions in heavy-ion collisions. We present measurements of the variances and covariance of [p_T] and v²_n, along with their dimensionless ratio, for Au+Au collisions at various beam energies: √s_NN = 14.6, 19.6, 27, 54.4, and 200 GeV. Our measurements reveal a distinct energy-dependent behavior in the variances and covariance. In addition, the dimensionless ratio displays a similar behavior across different beam energies. We compare our measurements with hydrodynamic models and similar measurements from Pb+Pb collisions at the Large Hadron Collider (LHC). These findings provide valuable insights into the beam energy dependence of the specific shear viscosity (η/s) and initial-state effects, allowing for differentiating between different initial-state models.

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