Transverse Dynamics of Strange Hadrons in Relativistic Heavy-Ion Collisions

We present a study of the mean transverse momentum of identified strange hadrons () produced in Au+Au collisions at RHIC-BES energies (the nucleon–nucleon center-of-mass energyand ). The mean transverse momentum is obtained from transverse momentum spectra of the strange hadrons as measured by the STAR experiment and its dependence on the number of participants is studied. For RHIC-BES energies, experimental data indicate a centrality dependence of , with an increase towards central collisions. This dependency is described using a power-law function to fit the data. The power-law exponent is used to characterize the degree of flattening of with respect to and its dependency on the collision energy and particle mass is studied. Special emphasis is placed on -meson that has a smaller interaction cross-section, thus reflecting the properties of the early stages of the system’s evolution. The of -mesons produced in Au+Au collisions at RHIC-BES energies are compared with the results obtained in Au+Au collisions at higher RHIC energies and in Pb+Pb collisions at SPS and LHC energies. A distinct energy dependence of values is identified. Furthermore, data indicate, when comparing peripheral and central heavy-ion collisions, that -meson increases with system size, following two distinct trends. The results are compared with the predictions of the default and string-melting versions of the AMPT generator. We observe that the string-melting AMPT version describes the strange meson , but underpredicts the strange baryon centrality dependence. The default AMPT overpredicts the and meson centrality dependence, while the strange baryon data are in general better described by this version of the model. The exponent obtained from AMPT-simulated results does not describe the measurements satisfactorily.