# Differential flow correlations in relativistic heavy-ion collisions

## TL;DR

This paper systematically analyzes correlations between different orders of transverse momentum differential flow in heavy-ion collisions, revealing how mode coupling effects and event-plane correlations relate to flow vectors and eccentricities.

## Contribution

It extends previous studies by analyzing differential flow correlations, mode coupling effects, and event-plane correlations, highlighting their dependence on flow vectors and eccentricities.

## Key findings

- Mode coupling effects mirror those of integrated flows at high transverse momentum.
- Event plane correlations for $V_4$ and $V_5$ relate to mode coupling contributions.
- Linear response of $V_4$ and $V_5$ scales with cumulant-defined eccentricities.

## Abstract

A systematic analysis of correlations between different orders of $p_T$-differential flow is presented, including mode coupling effects in flow vectors, correlations between flow angles (a.k.a. event-plane correlations), and correlations between flow magnitudes, all of which were previously studied with integrated flows. We find that the mode coupling effects among differential flows largely mirror those among the corresponding integrated flows, except at small transverse momenta where mode coupling contributions are small. For the fourth- and fifth-order flow vectors $V_4$ and $V_5$ we argue that the event plane correlations can be understood as the ratio between the mode coupling contributions to these flows and and the flow magnitudes. We also find that for $V_4$ and $V_5$ the linear response contribution scales linearly with the corresponding cumulant-defined eccentricities but not with the standard eccentricities.