Particle Correlations in Jets

Abstract: We study particle correlations in high energy jets by comparing the measured energy-energy correlator (EEC) with that constructed from two individual energy flows with respect to the jet axis. This comparison demonstrates that genuine correlations exists for small angle and moderate/large angle, indicating that they are coming from correlated splitting. This method will provide a unique tool to disentangle different physics, by comparing the genuine correlations in jet EEC between heavy ion collisions and proton-proton collisions. It will help to expose the medium modification of parton splitting in hot QCD medium. On the other hand, the medium responses are expected to be canceled out in the genuine correlations.