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arXiv · 0911.0811

Trying to understand the ridge effect in hydrodynamic model

Yogiro Hama·Rone Peterson G. Andrade·Frederique Grassi·Wei-Liang Qian
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Abstract

In a recent paper, the hydrodynamic code NeXSPheRIO was used in conjunction with STAR analysis methods to study two-particle correlations as function of Delta_eta and Delta_phi. Both the ridge-like near-side and the double-hump away-side structures were obtained. However, the mechanism of ridge production was not clear. In order to understand it, we study a simple model with only one high-energy density peripheral tube in a smooth cylindrical back-ground, with longitudinal boost invariance. The results are rather surprising, but the model does produce the triple-ridge structure with one high ridge plus two lower ones placed symmetrically with respect to the former one. The shape of this structure is rather stable in a wide range of parameters.

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Yogiro Hama, Rone Peterson G. Andrade, Frederique Grassi, Wei-Liang Qian. 2009-11-04. Trying to understand the ridge effect in hydrodynamic model. https://arxiv.org/abs/0911.0811

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