Thursday·June 25, 2020

[Submitted on 23 Jun 2020]

Probing the structure of the initial state of heavy-ion collisions with $p_T$-dependent flow fluctuations

Maurício Hippert🇧🇷 · João Guilherme Prado Barbon🇧🇷 · David Dobrigkeit Chinellato🇧🇷 · Matthew Luzum🇧🇷 · Jorge Noronha🇺🇸 · Tiago Nunes da Silva🇧🇷 · Willian Matioli Serenone🇧🇷 · Jun Takahashi🇧🇷

The connection between initial-state geometry and anisotropic flow can be quantified through a well-established mapping between $p_T$-integrated flow harmonics and cumulants of the initial transverse energy distribution. In this paper we successfully extend this mapping to also include $p_T$-differential flow. In doing so, we find that subleading principal components of anisotropic flow can reveal previously unobserved details of the hydrodynamic response, in both the linear and the nonlinear regimes. Most importantly, we show that they provide novel information on the small-scale structures present in the initial stage of relativistic heavy-ion collisions.