Speaker
Description
Correlations between event-by-event mean transverse momentum, $[p_T]$, and elliptic flow, $v_2$, reflect how fluctuations in the initial state influence the final particles produced in heavy-ion collisions. We calculate higher-order mixed cumulants of these observables using relativistic viscous hydrodynamics and compare them with event-by-event predictors constructed from the initial entropy distribution. The predictors quantitatively reproduce the centrality dependence of the higher-order cumulants obtained in the hydrodynamic simulations.
We also derive quantitative relations between cumulants of $[p_T]$ and different moments of harmonic flow. These relations are well satisfied by the hydrodynamic results and can be tested with experimental data. They offer a way to examine whether the observed correlations between mean transverse momentum and flow arise from collective evolution.