Radiative energy loss of hard parton jet in expanding quark-gluon fluid

The gluon radiation induced by multiple scattering of a hard parton in expanding quark-gluon plasma is investigated. The radiative energy loss of hard parton jet is shown to decrease considerably when angular size of extracted jet goes up, but the fraction of loss survives even for the reasonable wide cone of angles due to the coherent effects taking into account the rescattering of the radiated gluons in the QCD medium. The possible application to the jet quenching phenomenon in heavy ion collisions at LHC energies is discussed.