Jet Quenching Meets Gluon Saturation

Abstract

We present a theoretical framework for jet fragmentation in heavy-ion collisions based on the resummation of large energy logarithms. Exploiting the hierarchy of scales characteristic of jet quenching, we show that the jet function obeys the Banfi-Marchesini-Smye evolution equation, with medium-induced energy loss and color decoherence encoded in the initial condition. This structure reveals a close correspondence with saturation physics. In particular, the coherence angle emerges as the analog of the saturation scale and exhibits the same asymptotic scaling behavior under nonlinear evolution. As a proof of principle, we compute the jet nuclear modification factor to quantify the interplay between vacuum radiation and medium-induced color decoherence. Our framework provides a unified perturbative description of vacuum-like parton showers, medium-induced radiation, and color-coherence effects, paving the way for precision studies of jet quenching at RHIC and the LHC.