The "Shoulder" and the "Ridge" in PHENIX

Abstract

The observation of jet quenching in ultra-relativistic heavy ion collisions demonstrates significant energy loss of fast partons when passing through the created medium. Correlations between final-state particles at intermediate transverse momentum (1.0 $\lesssim$ $p_T$ $\lesssim$ 4.0 GeV/$c$) allow for study of the medium and its response to deposited energy. Comparison of these measurements in heavy ion collisions with measurements in proton collisions show strong modification of the correlation shape and particle yields. Two new structures are created, both extended in $\Delta \eta$, one centered at $\Delta \varphi =0$ (``ridge'') and the other occurring at $\Delta \varphi \approx \pi \pm 1.1$ (``shoulder''). In these proceedings, we describe the measurements of these structures that show consistency with a scenario of parton-medium interaction and response. We discuss a new analysis which selects on the angle of trigger particles relative to the reaction plane in Run7. New measurements of the centrality and $p_T$ dependencies of the structures raise the possibility that the same production mechanism may give rise to both phenomena.

4 pages, 4 figures, Quark Matter 2008 conference proceedings

References in corpus (2)

• System Size and Energy Dependence of Jet-Induced Hadron Pair Correlation Shapes in Cu+Cu and Au+Au Collisions at sqrt(s_NN) = 200 and 62.4 GeV
• Highlights from PHENIX - I

Cited by in corpus (17)

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• Momentum Kick Model Analysis of PHENIX Near-Side Ridge Data and Photon Jet
• Highlights from PHENIX - I
• Two-particle correlations at high-energy nuclear collisions, peripheral-tube model revisited
• Longitudinal dependence of two-particle momentum correlations from NEXSPHERIO model
• Away-side asymmetry of jet correlation relative to reaction plane: a sensitive probe for jet in-medium modifications
• Bose-Einstein Interference in the Passage of a Jet in a Dense Medium
• Feynman Amplitude Approach to study the Passage of a Jet in a Medium
• Effects of Jets in the Flow Observables
• Novel Bose-Einstein Interference in the Passage of a Fast Particle in a Dense Medium
• Analysis of the near-side ridge structure in pp collisions via Momentum-Kick Model