We report the transverse momentum ($p_{ \mathrm{ T}}$) and centrality dependence of global spin alignment ($\rho_{ 00}$) of $K^{ *0}$ vector meson at midrapidity ($|y|<0.5$) in Au + Au collisions at $\sqrt{ s_{ NN}}$ = 54.4 and 200~GeV with the STAR experiment at RHIC. The $K^{ *0}$ results are compared to that of $\phi$ meson. At low-$p_{ \mathrm{ T}}$ region and midcentral collisions, the $K^{ *0}$ $\rho_{ 00}$ is found to be smaller than 1/3 with about 4$\sigma$ significance, while that of $\phi$ meson is observed to be larger than 1/3 with about 3$\sigma$ significance. The $\rho_{ 00}$ results are compared between RHIC and LHC energies. The physics implication of our results is also discussed.
Categories: nucl-ex hep-ex nucl-th