An Equilibrating Parton Shower for Jet Quenching and Medium Response

Abstract

In the weak-coupling approach, thermalization of the quark-gluon plasma and the evolution of jet-like perturbations in the medium can be described by the same underlying QCD effective kinetic theory (EKT). In this work, we show how the EKT reduces to the standard energy-loss and angular-broadening evolution of jet-quenching in the high-energy regime, while providing a consistent description near the thermal scales. Building on this, we derive a parton shower directly from EKT that reproduces the full linearized Boltzmann equation, combining elastic and inelastic collisions to capture both hard-parton energy loss and thermal equilibration on an equal footing. This shower lets us extend EKT to inhomogeneous perturbations, connecting jet evolution to the medium's hydrodynamic response, including wakes, Mach cones, and multi-particle correlations.