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Fractional Energy Loss and Centrality Scaling

Rudolph C. Hwa·C. B. Yang
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Abstract

The phenomenon of centrality scaling in the high-\pt spectra of $π^0$ produced in Au-Au collisions at $\sqrt s=200$ GeV is examined in the framework of relating fractional energy loss to fractional centrality increase. A new scaling behavior is found where the scaling variable is given a power-law dependence on $N_{\rm part}$. The exponent $γ$ specifies the fractional proportionality relationship between energy loss and centrality, and is a phenomenologically determined number that characterizes the nuclear suppression effect. The implication on the parton energy loss in the context of recombination is discussed.

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Rudolph C. Hwa, C. B. Yang. 2003-07-29. Fractional Energy Loss and Centrality Scaling. https://doi.org/10.1103/physrevc.69.034902

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