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Centrality Scaling of the $p_T$ Distribution of Pions

Rudolph C. Hwa·C. B. Yang
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Abstract

From the preliminary data of PHENIX on the centrality dependence of the $π^0$ spectrum in $p_T$ at midrapidity in heavy-ion collisions, we show that a scaling behavior exists that is independent of the centrality. It is then shown that $ $ degrades with increasing $N_{\rm part}$ exponentially with a decay constant that can be quantified. A scaling distribution in terms of an intuitive scaling variable is derived that is analogous to the KNO scaling. No theoretical models are used in any part of this phenomenological analysis.

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Rudolph C. Hwa, C. B. Yang. 2003-01-06. Centrality Scaling of the $p_T$ Distribution of Pions. https://doi.org/10.1103/physrevlett.90.212301

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