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arXiv · hep-ph/0406201

Leading-particle suppression in high energy nucleus-nucleus collisions

Abstract

Parton energy loss effects in heavy-ion collisions are studied with the Monte Carlo program PQM (Parton Quenching Model) constructed using the BDMPS quenching weights and a realistic collision geometry. The merit of the approach is that it contains only one free parameter that is tuned to the high-pt nuclear modification factor measured in central Au-Au collisions at sqrt{s_NN} = 200 GeV. Once tuned, the model is coherently applied to all the high-pt observables at 200 GeV: the centrality evolution of the nuclear modification factor, the suppression of the away-side jet-like correlations, and the azimuthal anisotropies for these observables. Predictions for the leading-particle suppression at nucleon-nucleon centre-of-mass energies of 62.4 and 5500 GeV are calculated. The limits of the eikonal approximation in the BDMPS approach, when applied to finite-energy partons, are discussed.

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A. Dainese, C. Loizides, G. Paic. 2004-11-04. Leading-particle suppression in high energy nucleus-nucleus collisions. https://doi.org/10.1140/epjc%2Fs2004-02077-x

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