Jet modification via π0-hadron correlations in Au + Au collisions at √sNN = 200 GeV

Abstract

High-momentum two-particle correlations are a useful tool for studying jet-quenching effects in the quark-gluon plasma. Angular correlations between neutral-pion triggers and charged hadrons with transverse momenta in the range 4–12 GeV/𝑐 and 0.5–7 GeV/𝑐, respectively, have been measured by the PHENIX experiment in 2014 for Au+Au collisions at √𝑠𝑁⁢𝑁=200 GeV. Suppression is observed in the yield of high-momentum jet fragments opposite the trigger particle, which indicates jet suppression stemming from in-medium partonic energy loss, while enhancement is observed for low-momentum particles. The ratio and differences between the yield in Au+Au collisions and 𝑝+𝑝 collisions, 𝐼𝐴⁢𝐴 and Δ𝐴⁢𝐴, as a function of the trigger-hadron azimuthal separation, Δ⁢𝜙, are measured for the first time at the BNL Relativistic Heavy Ion Collider. These results better quantify how the yield of low-𝑝𝑇 associated hadrons is enhanced at wide angle, which is crucial for studying energy loss as well as medium-response effects.