System-size dependence of transverse momentum correlations at √sNN = 62.4 and 200 GeV at the BNL Relativistic Heavy Ion Collider

Abstract

We present a study of the average transverse momentum (pt) fluctuations and pt correlations for charged particles produced in Cu+Cu collisions at midrapidity for √sNN= 62.4 and 200 GeV. These results are compared with those published for Au+Au collisions at the same energies, to explore the system size dependence. In addition to the collision energy and system size dependence, the pt correlation results have been studied as functions of the collision centralities, the ranges in pt, the pseudorapidity η, and the azimuthal angle ϕ. The square root of the measured pt correlations when scaled by mean pt is found to be independent of both colliding beam energy and system size studied. Transport-based model calculations are found to have a better quantitative agreement with the measurements compared to models which incorporate only jetlike correlations.