Phenomenological models of two-particle correlations on transverse momentum in relativistic heavy-ion collisions

Two-particle correlations on (pt1,pt2) constructed from the particle production in relativistic heavy-ion collisions allow unique access to soft, semi-hard and hard-scattering processes in these systems. In this talk two phenomenological models which describe these correlations are presented and the results compared to data. One model is based on an event-by-event fluctuating blast wave. The other is based on an event-by-event fluctuating color-string plus jet fragmentation approach. Both models are capable of accurately describing the measured single-particle pt distributions for minimum-bias Au+Au collisions at 200 GeV as a function of collision centrality. The models are also applied to estimates of preliminary, charged-particle correlation measurements. Overall, both of these new, phenomenological approaches are capable of qualitatively describing these correlation structures and will provide useful tools for interpreting the centrality trends in future correlation data from the RHIC. Predictions of an event-by-event hydrodynamical model (EPOS) and the fragmentation-based model (HIJING) are compared to each other and to data.