Two particle correlation measurements with respect to higher harmonic event planes at PHENIX

TL;DR

This paper presents PHENIX measurements of two-particle azimuthal correlations in heavy ion collisions, focusing on higher harmonic flow subtraction and event plane dependence to study parton-medium interactions.

Contribution

It introduces correlation measurements that isolate higher harmonic flow effects and analyze path-length dependence of parton energy loss relative to event planes.

Findings

Higher harmonic flow contributions are successfully subtracted.

Correlation patterns depend on the event plane orientation.

Results provide insights into medium effects on jets.

Abstract

Measurements of two particle azimuthal correlations in relativistic heavy ion collisions provide information of the possible interplay between hard-scattered partons and the hot-dense medium. Toward an understanding of parton-medium coupling, it is indispensable to obtain correlations where contributions from higher harmonic flow($v_n$) are rejected. It is also important to produce correlation measurements where the trigger particle is selected relative to second and third order event planes. This enables us to explore path-length dependence of parton energy loss and the influence of the medium on the jets. We present the latest PHENIX results of correlations in which contributions from higher harmonic flow have been subtracted, as well as second and third order event plane-dependent correlations in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV.