Speaker
Description
We study the hydrodynamization process in the aftermath of ultrarelativistic heavy-ion collisions using effective kinetic theory simulations and different observables. For the pressure ratio $P_T/P_L$, we observe that its late-time evolution becomes universal in units of the kinetic relaxation time for sufficiently large couplings signaling the onset of a hydrodynamical attractor. In contrast, at weak couplings, it converges earlier to a bottom-up attractor in terms of the thermalization time scale $\tau_{\text{BMSS}} = \alpha_s^{-13/5}/Q_s$. We interpret these as two limiting attractors. The dynamics of the occupancy of hard modes, the heavy-quark diffusion coefficient, and the jet quenching parameter are better described by a bottom-up limiting attractor even for moderate couplings. Therefore, the previous conjecture that the hydrodynamical attractor governs the late-time approach toward hydrodynamization is not complete. Our results rather indicate that a weak coupling attractor emerges additionally in the coupling regime relevant for heavy-ion collisions for certain observables.
| Category | Theory |
|---|
