Pre-hydrodynamic jet momentum broadening beyond the jet quenching parameter

Abstract

We obtain the collision kernel and related dipole cross section during the initial nonequilibrium stages in heavy-ion collisions. These quantities are a crucial input for jet quenching calculations. We further compute the gluon splitting rates in the AMY formalism resulting from this nonequilibrium kernel. Comparing with thermal and commonly used forms, we find that particularly the gluon splitting rate for parton energies of the order of the hard effective temperature significantly differs from these approximations.

Comments: 4 pages, 2 figures; Quark Matter 2025 conference proceedings