Investigating the origin of the long range pseudo rapidity correlation   in 2d di-hadron measurements from STAR
  Angular di-hadron correlations reveal novel structures in central Au+Au collisions at $\sqrt{S_{NN}}$ = 200 GeV. One of them, known as the ridge, is elongated in pseudo rapidity and peaks on the near side ($\Delta\phi$ $\approx$ 0). Investigating the origin of the ridge structure helps to understand the hot dense matter that is created in ultra relativistic heavy ion collisions. Results showing the $<$$p_{T}$$>$ dependence of the ridge structure are presented. Evidence for possible jet and non-jet contributions to the ridge structure will be discussed. 
L. C. De Silva (for the STAR collaboration)
nucl-ex hep-ex