beam-energy and collision-system dependence of flow correlations and fluctuations in heavy-ion collisions

Investigations of flow correlations and fluctuations in heavy-ion collisions can give in-depth insights into the expansion dynamics of these collisions. They can also provide new constraints for initial-state models to allow robust extraction of the specific shear viscosity $\eta/s$. The recent STAR differential measurements of the flow correlations (symmetric cumulants) and the flow-momentum correlations, $\rho(v^{2}_{n},\langle p_{T} \rangle)$~[1], will be presented for several collisions-systems at different beam energies. The results show characteristic system- and beam-energy-dependent trends which are compared with similar LHC measurements~[2,3] as well as calculations from several viscous hydrodynamic models. The comparisons between data and theoretical calculations show that the measurements can be used to pin down the respective influence of initial-state fluctuations, system-size, shape ($\varepsilon$), and $\eta/s(T)$. The implications of the constraining power of these measurements will be discussed.\\ ~\\ [1]~Piotr Bozek, Transverse momentum-flow correlations in relativistic heavy-ion collisions, Phys. Rev. C {\bf 93}, 044908 (2016).\\ [2]~ATLAS Collaboration, Measurement of flow harmonics correlations with mean transverse momentum in lead-lead and