Can Tsallis Distribution Fit All the Particle Spectra Produced at RHIC and LHC?

الملخص EN

The Tsallis distribution has been tested to fit all the particle spectra at mid-rapidity from central events produced in d + Au, Cu + Cu, and Au + Au collisions at RHIC and p + Pb, Pb + Pb collisions at LHC.

Even though there are strong medium effects in Cu + Cu and Au + Au collisions, the results show that the Tsallis distribution can be used to fit most of particle spectra in the collisions studied except in Au + Au collisions where some deviations are seen for proton and Λ at low p T .

In addition, as the Tsallis distribution can only fit part of the particle spectra produced in Pb + Pb collisions where p T is up to 20 GeV/c, a new formula with one more fitting degree of freedom is proposed in order to reproduce the entire p T region.