Speaker
Description
Using the holographic model, we study mass spectrum and spin alignment for $J/\Psi$ mesons propagating through an anisotropic plasma. Our results show that the invariant mass of $J/\Psi$ decreases, while its decay width increases with increasing $J/\Psi$'s momentum or increasing temperature. We observe that longitudinal and transverse modes have different mass spectra due to the broken radial symmetry in the rest frame of $J/\Psi$, leading to different particle number densities that can be measured through the spin alignment. We show that the spin alignment in the helicity frame is significantly smaller than 1/3, which is qualitatively consistent with the LHC data. The deviation from 1/3 demonstrates a non-monotonic dependence on the meson's momentum. Additionally, we have examined the impact of an anisotropic background, which is expected to be closer to the real QGP matter.
