We investigate the impacts of intrinsic nuclear deformation and orientation on the yield suppression and momentum anisotropy of charmonia in $\mathrm{Au}+\mathrm{Au}$ and $\mathrm{U}+\mathrm{U}$ collisions at the Relativistic Heavy-Ion Collider (RHIC). The deformed nucleon density is parametrized via a modified Woods-Saxon distribution, which self-consistently determines the initial spatial distributions of both the heavy quarkonia and the bulk medium. A well-established Boltzmann-type transport equation is then utilized to describe the dynamical evolution of charmonia within this anisotropic medium. Using $\mathrm{Au}+\mathrm{Au}$ collisions as a baseline, we find that the momentum-integrated charmonium yield suppression in $\mathrm{U}+\mathrm{U}$ collisions is relatively insensitive to the initial nuclear geometry. In contrast, the elliptic flow ($v_2$) of charmonia is more sensitive to the nuclear deformation, which is inherently driven by specific collision configurations (e.g., tip-tip, body-body-$x$, and body-body-$y$ orientations). These configuration studies elucidate how the spatial orientation of deformed nuclei relative to the impact parameter dictates the initial geometric eccentricity, which subsequently translates into the final-state momentum anisotropy of charmonia. Notably, this orientation-induced effect is enhanced for the excited $\psi \left(2S\right)$ state, as its larger dissociation rate amplifies the azimuthal asymmetry in the path-integrated survival probability.

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• Jets & heavy flavor physics
• Quark-gluon plasma
• Relativistic heavy-ion collisions
• Transport in heavy-ion collisions