STAR measurements of dihadron azimuthal correlations (Δϕ) are reported in midcentral (20–60%) Au + Au collisions at √sNN = 200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane, ϕs = |ϕt − ψEP |. The elliptic (v2), triangular (v3), and quadratic (v4) flow harmonic backgrounds are subtracted using the zero yield at minimum (ZYAM) method. The results are compared to minimum-bias d + Au collisions. It is found that a finite near-side (|Δϕ| < π/2) long-range pseudorapidity correlation (ridge) is present in the in-plane direction (ϕs∼0). The away-side (|Δϕ| > π/2) correlation shows a modification from d + Au data, varying with ϕs. The modification may be a consequence of path-length-dependent jet quenching and may lead to a better understanding of high-density QCD.
Digital Object Identifier (DOI)
Agakishiev, H; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Averichev, G. S.; Fatemi, Renee H.; Fersch, Robert G.; Korsch, Wolfgang; Webb, G.; and Witzke, Wayne Otto, "Event-Plane-Dependent Dihadron Correlations with Harmonic vn Subtraction in Au + Au Collisions at √sNN=200 GeV" (2014). Physics and Astronomy Faculty Publications. 126.