Spin alignment of Quarkonia: A Possible Probe of a Deconfined QCD matter in Heavy-ion Collisions at TeV Energies

TL;DR

This paper explores how deconfined QCD matter affects quarkonium spin alignment in heavy-ion collisions, using a thermal rotating medium model to understand the influence of vorticity, magnetic fields, and anisotropy.

Contribution

It introduces a novel approach to estimate quarkonium spin alignment by solving the Schrödinger equation with medium modifications, considering spin coupling with vorticity and magnetic fields.

Findings

Vorticity enhances quarkonium spin alignment.

Magnetic fields and anisotropy alter spin observables in a state-dependent manner.

Results provide insights into spin transport phenomena in hot QCD matter.

Abstract

In this study, we investigate the influence of deconfined QCD matter on quarkonium spin alignment in ultra-relativistic heavy-ion collisions. We estimate the spin alignment of charmonium ($J/\psi$, and $\psi$(2S)) and bottomonium ($\Upsilon$(1S), and $\Upsilon$(2S)) states by calculating the energy eigenvalues in a thermal rotating medium. We solve the Schr\"odinger equation with a medium-modified color-singlet potential considering the coupling of spin with vorticity and magnetic field. Furthermore, we evaluate the effect of medium temperature, vorticity, magnetic field, and momentum-space anisotropy on the elements of the spin density matrix. Our findings reveal that vorticity increases the spin alignment, while the magnetic fields and anisotropy modify the observables in a state-dependent manner. These findings deepen our understanding of quarkonium spin alignment in an anisotropic magneto-vortical thermal medium, shedding light on spin transport phenomena in heavy-ion collisions.