2018/05/02 by Aleksi Kurkela, Aleksas Mazeliauskas, Jean-François Paquet +2 · 3 citations
Physics and Astronomy · #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevc.99.034910
published as Phys. Rev. C 99, 034910 (2019) · 45 pages, 27 figures, for the code of linear kinetic theory propagator KoMPoST used for this study see https://github.com/KMPST/KoMPoST
arxiv created 2018/05/02 · arxiv updated 2019/04/03
We develop a macroscopic description of the space-time evolution of the energy-momentum tensor during the pre-equilibrium stage of a high-energy heavy-ion collision. Based on a weak coupling effective kinetic description of the microscopic equilibration process (à la "bottom-up"), we calculate the non-equilibrium evolution of the local background energy-momentum tensor as well as the non-equilibrium linear response to transverse energy and momentum perturbations for realistic boost-invariant initial conditions for heavy ion collisions. We demonstrate how this framework can be used on an event-by-event basis to propagate the energy momentum tensor from far-from-equilibrium initial state models, e.g. IP-Glasma, to the time τhydro when the system is well described by relativistic viscous hydrodynamics. The subsequent hydrodynamic evolution becomes essentially independent of the hydrodynamic initialization time τhydro as long as τhydro is chosen in an appropriate range where both kinetic and hydrodynamic descriptions overlap. We find that for √sNN=2.76 TeV central Pb-Pb collisions, the typical time scale when viscous hydrodynamics with shear viscosity over entropy ratio η/s=0.16 becomes applicable is τhydro∼ 1 fm/c after the collision.