Evaluation of kinetic freeze-out properties in different relativistic heavy-ion collision systems at sNN=200 GeV

We present our analysis of the identified hadrons (π+, K+, and p) kinetic freeze-out properties in relativistic collisions at sNN=200 GeV. We analyze the transverse momentum spectra of these hadrons across various collision systems, such as copper–copper (Cu-Cu), zirconium–zirconium (Zr-Zr), ruthenium–ruthenium (Ru-Ru), uranium–uranium (U-U), and gold–gold (Au-Au) collisions, in distinct centrality intervals at the same center-of-mass energy using the modified Hagedorn model with embedded flow. The freeze-out parameters, namely the kinetic freeze-out temperature (T0), transverse flow velocity (βT), and the entropy-related parameter (n), are extracted. Taking T0 and βT as common, it is observed that in all the above collisions, T0, βT, and the parameter n diminish toward the periphery and are greater in central collisions. However, T0 in central collisions across all the systems remains unchanged, indicating a phase transition from hadronic matter to quark–gluon plasma. Furthermore, the temperature required for the phase transition across various systems is different. Large systems exhibit a shift in the potential start of the phase transition in peripheral collisions, which is intriguing. We also observe a direct relation between the extracted parameters and the system’s size.