Pedestal and peak structure in jet correlation

We study the correlation characteristics between particles in jets produced in heavy-ion collisions. In the framework of parton recombination we calculate the eta and phi distributions of a pion associated with a trigger particle. The origin of the pedestal in Delta eta is related to the longitudinal expansion of the thermal partons that are enhanced by the energy loss of hard partons traversing the bulk medium. The peaks in Delta eta and Delta phi are related to the same angular spread of the shower partons in a jet cone. No artificial short- or long-range correlations are put in by hand. A large part of the correlation between hadrons in jets is due to the correlation among the shower partons arising from momentum conservation. Recombination between thermal and shower partons dominates the correlation characterisitics in the intermediate-p(T) region.