Different non-extensive models for heavy-ion collisions

The transverse momentum (pT) spectra from heavy-ion collisions at intermediate momenta are described by non-extensive statistical models. Assuming a fixed relative variance of the temperature fluctuating event by event or alternatively a fixed mean multiplicity in a negative binomial distribution (NBD), two different linear relations emerge between the temperature, T, and the Tsallis parameter q−1. Our results qualitatively agree with that of G. Wilk. Furthermore we revisit the “Soft+Hard” model, proposed recently by G.G. Barnaföldi et.al., by a T-independent average pT2 assumption. Relevance of these two parameters is demonstrated. Finally we compare results with those predicted by another deformed distribution, using Kaniadakis' κ parametrization.