Jan 10 – 15, 2021
Weizmann Institute of Science
Asia/Jerusalem timezone
See you at IS2023 in Copenhagen in June 2023

Linear and non-linear flow coefficients from transport theory

Jan 13, 2021, 4:30 PM
Andrea’s room 1 (vDLCC)

Andrea’s room 1


oral Collective dynamics from small to large systems CD


Urs Wiedemann (CERN)


The observation of fluid-like behavior in nucleus-nucleus (AA), proton-nucleus (pA) and high-multiplicity proton-proton (pp) collisions motivates systematic studies of how different measurements approach their fluid-dynamic limit. We have developed numerical methods to solve the ultra-relativistic Boltzmann equation for systems of arbitrary size and transverse geometry. Here, we apply these techniques for the first time to the study of azimuthal flow coefficients $v_n$ including non-linear mode-mode coupling and to an initial condition with realistic event-by-event fluctuations. We show how both linear and non-linear response coefficients extracted from $v_n$ develop as a function of opacity
from free streaming to perfect fluidity. We note in particular that away from the fluid-dynamic limit, the signal strength of linear and non-linear response coefficients does not reduce uniformly, but that their hierarchy and relative size shows characteristic differences.

Primary authors

Bin Wu (CERN) Eero Aleksi Kurkela (CERN) Seyed Farid Taghavi (Technische Universitaet Muenchen (DE)) Urs Wiedemann (CERN)

Presentation materials