Unraveling QCD dynamics with heavy quark energy correlators

Abstract

Heavy-flavor jets and their substructure provide a unique window into the role of quark mass on QCD radiation and its modification in nuclear matter. In this work, we investigate heavy-quark energy-energy correlators (EECs) that are explicitly sensitive to mass effects, focusing on angular distributions, energy flow, and the dead-cone effect. We demonstrate how the finite mass of charm and bottom quarks reshapes the intra-jet radiation pattern, leading to characteristic suppression at small angles and measurable deviations from massless jet expectations. Using effective field theory analysis, we extend the calculation of these observables to reactions with nuclei to show that medium-induced radiation competes with vacuum mass suppression, resulting in a nontrivial modification of jet substructure. Specifically, we identify regimes where EECs are dominated by the heavy quark mass, leading to qualitatively and quantitatively different behavior of this observable in QCD matter. We discuss the charm and bottom jet energy-energy correlators modification in reactions with nuclei, and further demonstrate how the formalism can be tested in small collision system at current facilities.