Seminar in Hadronic Physics

Collision geometry fluctuations, triangular flow and two-particle correlations in heavy ion collisions

Burak Alver

MIT

A paradigm shift is currently occurring in the study of two-particle correlation in heavy ion collisions. Two anomalous correlation structures, “ridge” and “broad away side”, which were originally observed in jet studies, have recently been shown to be natural consequences of initial geometry fluctuations and consequent collective expansion. This advancement calls for a change in the language used to describe these structures: “participant triangularity” characterizes the triangular anisotropy of the initial nuclear overlap geometry and “triangular flow” quantifies the resulting collective phenomena. In this talk, I will introduce triangular flow, discuss recent calculations in hydrodynamics and transport theory and present a case for simultaneous measurement of elliptic and triangular flow in the LHC era. I will also briefly discuss the recent two particle correlation measurements relative to the event plane, in light of triangular flow.