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(Color Online) Identified particle transverse momentum spectra in Au+Au collisions at √ s NN = 200 GeV in0- 10% central (a) and in peripheral 60-80% collisions (b). The symbols represent experiment data points. The solid curves represent the TBW fit.  

(Color Online) Identified particle transverse momentum spectra in Au+Au collisions at √ s NN = 200 GeV in0- 10% central (a) and in peripheral 60-80% collisions (b). The symbols represent experiment data points. The solid curves represent the TBW fit.  

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We have implemented the Tsallis statistics in a Blast-Wave model (TBW) and applied it to midrapidity transverse-momentum spectra of identified particles measured at BNL Relativistic Heavy Ion Collider (RHIC). This new TBW function fits the RHIC data very well for pT<3 GeV/c. We observed that the collective flow velocity starts from zero in p+p and...

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... choose the Minuit in Root [50] to perform a least-χ 2 fit used in ref. [1]. Figure 1 shows the p T spectrum data to- gether with our fit results in two selected centrality bins (0-10% and 60-80%) in Au+Au collisions. The fit pa- rameters and χ 2 /DoF are tabulated in Tab. ...

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... Therefore we choose the Hagedorn model with the embedded flow to extract the parameters directly from the transverse momentum spectra of the particles. We also have other choices to choose from other models (such as the Blast wave model with Boltzmann Gibbs statistics [8][9][10], Blast wave model with Tsallis statistics [11,12], Tsallis distribution with transverse flow effect [13,14] and modified Hagedorn function with embedded [15][16][17]) for the extraction of kinetic freeze-out temperature and radial flow but they can not be used for the wide pT range. For instance, the Blast wave model with Boltzmann Gibb's statistics can be used for the low pT of 0-2 or 2.5 GeV/c, and the Blast wave model with Tsallis can be used up to a pT range of 0-6 GeV/c. ...
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