Energy and particle flow in three-jet and radiative two-jet events from hadronic Z decays

Abstract We report on a detailed study of the energy and particle flow in the event plane of three-jet events (q q g) and radiative two-jet events (q q γ) in hadronic Z decays recorded with the L3 detector. We find a significant decrease in particle and energy density in the angular region between quark and antiquark jets for q q g events as compared with q q γ events. Several QCD model predictions are compared with the observed effect.