(b) Correlation functions over azimuthal opening angle ?? between hadron pairs with wide rapidity separation ??~3.4; for the d+Au nuclear system and the p+p elementary system at RHIC energies of 200 GeV.
(e)Enhanced correlation at opposite side ??~p is due to elementary processes; but near-side ??~0 enhancement in d+Au must be due to created medium physics.
(e)Enhanced correlation at opposite side ??~p is due to elementary processes; but near-side ??~0 enhancement in d+Au must be due to created medium physics.
The Relativistic Heavy Ion Collider (RHIC) was used to search for the formation of hydrodynamic-like excited nuclear medium being created in d+Au collisions. The team, including members of the Heavy Ion Group in the ORNL Physics Division, found near-side azimuthal correlations that are not present in elementary p+p collisions. The pattern they measured could not be an elementary particle process, but is consistent with formation of a hydrodynamic, excited quark-gluon plasma (QGP). This work demonstrates excited medium formation in systems smaller than previously thought possible.