Speaker
Description
Relativistic heavy-ion collisions provide a unique setting to investigate QCD matter under varied temperatures and densities. As the collision energy rises, the baryon chemical potential ($\mu_{B}$) decreases, resulting in a mid-rapidity region rich in baryons at the lower Beam Energy Scan (BES) program energies and in mesons at top RHIC energies. Short-lived resonances like $K^{*0}$ (lifetime $\sim$ 4.16 fm/$c$) are effective probes of the hadronic medium. As they primarily decay within the fireball, their decay products undergo in-medium effects like rescattering and regeneration, potentially modifying $K^{*0}$ properties. However, due to change in the chemical composition of the system produced at low and high collision energies, distinct difference in the particle interaction can be expected. The measurement of $K^{*0}$ meson over a broad collision energy range will help shed light on this phenomenon.
In this presentation, we will report precision measurements of $K^{*0}$ mesons in isobar (Zr+Zr and Ru+Ru) collisions at $\sqrt{s_{NN}}$ = 200 GeV and in Au+Au collisions at $\sqrt{s_{NN}}$ =7.7,11.5,14.6,19.6, and 27 GeV, using high-statistics STAR BES-II data. Results will include transverse momentum ($p_{T}$) spectra, yields ($dN/dy$), and mean transverse momentum ($\langle p_{T}\rangle$). Additionally, the $K^{*0}/K$ ratio as a function of multiplicity across different systems and energies will be discussed, providing insights into the underlying physics of the hadronic medium.
