Observation of non-homogeneous scenarios for different temperatures in hadron(nucleus)-nucleus collisions at RHIC and LHC energies

We used the modified Hagedorn function and analyzed the experimental data measured by the BRAHMS, STAR, PHENIX, and ALICE Collaborations in Copper–Copper, Gold–Gold, deuteron–Gold, Lead–Lead, proton–Lead and proton–proton collisions, and extracted the related parameters (kinetic freezeout temperature, transverse flow velocity, kinetic freezeout volume, mean transverse momentum, and initial temperature) from the transverse momentum spectra of the particles (non-strange and strange particles). We observed that all the above parameters increase from peripheral to central collisions, except transverse flow velocity, which remains unchanged. The kinetic freezeout temperature depends on the particle's interaction cross-section such that a larger cross-section corresponds to a smaller T₀ and reveals the two kinetic freezeout scenarios. Similarly, the initial temperature follows the mass dependency of the particle, and it increases with the particle mass. The transverse flow velocity and mean transverse momentum depend on the particle's specie. The former decreases while the latter increases for the massive particles. Furthermore, different freezeout surfaces for different particles are observed as the kinetic freezeout volume decreases for the heavier particles. We also extracted the entropy index-parameter “n” and the parameter N₀, the former remains almost unchanged while the latter decreases from central collisions to the periphery. Furthermore, the kinetic freezeout temperature, transverse flow velocity, kinetic freezeout volume, initial temperature, mean transverse momentum and the parameter N₀ at LHC are larger than that of RHIC, showing their dependence on the collision cross-section and collision energy.