Spin alignment of vector mesons from quark dynamics in a rotating medium* *Supported in part by the National Natural Science Foundation of China (NSFC) (12235016, 12221005), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB34030000), the start-up funding from the University of Chinese Academy of Sciences (UCAS), and the Fundamental Research Funds for the Central Universities

Abstract

Vorticities in heavy-ion collisions (HICs) are supposed to induce spin alignment and polarization phenomena of quarks and mesons. In this work, we analyze the spin alignment of vector mesons ϕ and ρ induced by rotation from quark dynamics in the framework of the Nambu-Jona-Lasinio (NJL) model. The rotating angular velocity induces mass splitting of spin components for vector mesons . This behavior contributes to the spin alignment of vector mesons in an equilibrium medium and naturally explains the negative deviation of for vector mesons. Incidentally, the positive deviation of under the magnetic field can also be easily understood from quark dynamics.