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arXiv · 0705.3238

Transverse momentum and centrality dependence of dihadron correlations in Au+Au collisions at sqrt(s_NN)=200 GeV: Jet-quenching and the response of partonic matter

PHENIX Collaboration·A. Adare
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Abstract

Azimuthal angle Δϕcorrelations are presented for charged hadrons from dijets for 0.4 < p_T < 10 GeV/c in Au+Au collisions at sqrt(s_NN) = 200 GeV. With increasing p_T, the away-side distribution evolves from a broad to a concave shape, then to a convex shape. Comparisons to p+p data suggest that the away-side can be divided into a partially suppressed "head" region centered at Deltaϕ~ π, and an enhanced "shoulder" region centered at Deltaϕ~ π+/- 1.1. The p_T spectrum for the "head" region softens toward central collisions, consistent with the onset of jet quenching. The spectral slope for the "shoulder" region is independent of centrality and trigger p_T, which offers constraints on energy transport mechanisms and suggests that the "shoulder" region contains the medium response to energetic jets.

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PHENIX Collaboration, A. Adare. 2007-05-22. Transverse momentum and centrality dependence of dihadron correlations in Au+Au collisions at sqrt(s_NN)=200 GeV: Jet-quenching and the response of partonic matter. https://doi.org/10.1103/physrevc.77.011901

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