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arXiv · 2402.16550

Hexadecapole deformation of $^{238}$U from relativistic heavy-ion collisions using a nonlinear response coefficient

Hao-jie Xu·Jie Zhao·Fuqiang Wang
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Abstract

The hexadecapole deformation ($\beta_4$) of the $^{238}$U nucleus has not been determined because its effect is overwhelmed by those from the nucleus' large quadrupole deformation ($\beta_2$) in nuclear electric transition measurements. In this Letter, we identify the nonlinear response of the hexadecapole anisotropy to ellipticity in relativistic $^{238}$U+ $^{238}$U collisions that is solely sensitive to $\beta_4$ and insensitive to $\beta_2$. We demonstrate this by state-of-the-art hydrodynamic calculations and discuss the prospects of discovering the $\beta_4$ of $^{238}$U in heavy-ion data at the Relativistic Heavy Ion Collider.

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Hao-jie Xu, Jie Zhao, Fuqiang Wang. 2024-02-26. Hexadecapole deformation of $^{238}$U from relativistic heavy-ion collisions using a nonlinear response coefficient. https://doi.org/10.1103/physrevlett.132.262301

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