Mode-by-mode evolution of Pb-Pb collisions at 5.02 TeV in a hybrid model

TL;DR

This paper analyzes the evolution of fluctuation modes in Pb-Pb collisions at 5.02 TeV, revealing how initial state fluctuations influence final observables through a hybrid modeling approach.

Contribution

It introduces a mode-by-mode analysis of initial state fluctuations and their impact on collision observables using a hybrid evolution model.

Findings

Modes in narrow central bins resemble fixed impact parameter events

Impact-parameter variation affects modes in mid-peripheral collisions

Hadronic transport cascade implementation is feasible but computationally costly

Abstract

We determine the average state and the uncorrelated modes that characterize the event-by-event fluctuations of the initial state in two typical centrality classes of Pb-Pb collisions at 5.02 TeV. We find that modes in a narrow central bin are similar to those in events at fixed vanishing impact parameter, while those in a mid-peripheral centrality class are affected by the impact-parameter variation. We study how each fluctuation mode affects observables both in the initial state and in the final state of the collisions, at the end of a state-of-the-art boost-invariant hybrid evolution with KoMPoST + MUSIC + iSS + SMASH, and show that implementing a hadronic transport cascade in such a mode-by-mode analysis with reasonable statistical noise is costly but feasible.