Speaker
Description
Traditional Monte Carlo Glauber models[1] treat deformed nuclei using a classical approximation: in each event, a fixed orientation is randomly assigned to the nucleus, which effectively breaks the rotational symmetry. However, for even-even nuclei, the ground state must remain in the $J=0$ ground state. To restore this broken symmetry, we introduce quantum superposition over all possible orientations[2]. This approach ensures the nucleus is correctly described as a symmetry-restored state rather than a classically fixed configuration.
In this talk, we use the same approach[2] to restore the entangled ground state and investigate the impact on final-state observabels in in Ne+Ne, Si+Si, Ru+Ru, and U+U collisions. In addition to the two-particle flow coefficients, $v_n\{2\}$, we investigate the normalized symmetric cumulants (NSCs) and the Pearson correlation which are sensitive to nuclear structure and can be used to constrain nuclear deformation parameters[3].
Our results show that, in central Ne+Ne collisions, $v_2$ is reduced by approximately $13\%$ in the quantum-superposition configuration relative to the classical configuration, and in U+U collisions, the corresponding reduction is approximately $5\%$. Quantum effects are also pronounced in the cross-system ratios of the covariance numerator, which are defined generically as
$
R_{X/Y}
=
\frac{
\left\langle v_2^2\,\delta[p_T]\right\rangle_{X}
}{
\left\langle v_2^2\,\delta[p_T]\right\rangle_{Y}
}.
$
For the strongly deformed prolate systems Ne+Ne and U+U, the corresponding ratios, $R_{\mathrm{Ne+Ne}/\mathrm{O+O}}$ and $R_{\mathrm{U+U}/\mathrm{Au+Au}}$, change from approximately $1.9$ to $0.9$ and from approximately $-3.1$ to $-1.4$, respectively. The above results indicate that considering a symmetry-restored description of the nuclear ground state can have important implications for extracting nuclear-structure information and constraining QGP properties in both light- and heavy-ion collisions.
[1] M.L. Miller, K. Reygers, S.J. Sanders, P. Steinberg, Ann. Rev. Nucl. Part. Sci. 57 (2007) 205.
[2] W. Ke, arXiv:2509.09549 [nucl-th] (2025).
[3] M.I. Abdulhamid, et al. (STAR Collaboration), Nature 635 (2024) 67.
| Academic Status | I am a Ph.D. student |
|---|
