The moving orientation effect (MOE) in nuclear collisions has been investigated through barrier distributions. To this end, the experimental barrier distributions for systems with a spherical medium-mass target nucleus (${}^{90}\mathrm{Zr}$) and two different deformed projectiles, ${}^{24}\mathrm{Mg}$ and ${}^{28}\mathrm{Si}$, with prolate (${}^{24}\mathrm{Mg}$) and oblate (${}^{28}\mathrm{Si}$) deformations, were analyzed within the framework of coupled-channels (CC) calculations. It is observed that the MOE is mainly driven by the nuclear rotational coupling of the moving projectiles in the field of stationary, heavy, and spherical target. The change in the shape of barrier distribution due to the MOE depends on the ground-state deformations, that is, the quadrupole (${\beta }_2$) and hexadecapole (${\beta }_4$) deformations of the deformed projectiles. A reduction in fusion cross sections for free orientations with respect to frozen cases was observed, which is more in the case of prolate than the oblate deformations irrespective of the value and the sign of ${\beta }_4$. This is primarily because the effective rotational energy is larger for the prolate than the oblate shapes. These results may have a direct bearing to the nuclear collisions for synthesis of superheavy elements involving nearly spherical target and axially deformed projectile.

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• Low & intermediate energy heavy-ion reactions
• Nuclear fusion
• Nuclear reactions
• Synthesis of new superheavy elements