Pranjal Barik, Kadambini Menduli, A. K. Sahoo, Md. Nasim
We present the yield, average transverse momentum, and collective flow calculations of K * 0 resonances in Au + Au collisions at s N N = 19.6 , 14.5, and 7.7 GeV using the AMPT model. It is found that, due to hadronic rescattering, the decay daughters of K * 0 interact with other particles in the medium, causing the yield of reconstructable K * 0 to be significantly suppressed, especially at low transverse momentum. The model results are compared with recent experimental data from Phase-II of the Beam Energy Scan (BES-II) program at the Relativistic Heavy-Ion Collider. The string-melting version of the AMPT model successfully reproduces the measured K * 0 / K ratios at all three analyzed collision energies. Interestingly, AMPT calculations that exclude the hadronic phase nevertheless provide a reasonable description of the data, thereby challenging the conventional interpretation that hadronic rescattering is the primary mechanism responsible for suppressing the K * 0 / K ratio in central heavy-ion collisions. In addition, we find that the K * 0 / K ratio appears to be largely insensitive to the lifetime of the hadronic phase, whereas the average transverse momentum, 〈 p T 〉 , of the K * 0 shows a strong dependence, increasing significantly as the lifetime of the hadronic phase becomes longer. We further show that the directed flow ( v 1 ) of K * 0 mesons is strongly influenced by hadronic rescattering, whereas the elliptic flow ( v 2 ) exhibits only weak sensitivity to hadronic effects. These results establish K * 0 directed flow as a sensitive probe of the late-stage hadronic medium in heavy-ion collisions. These model calculations therefore provide valuable insight into the underlying physics governing the observed experimental results at RHIC.