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arXiv · 2312.13572

Probing configuration of $\alpha$ clusters with spectator particles in relativistic heavy-ion collisions

Lu-Meng Liu·Song-Jie Li·Zhen Wang·Jun Xu·Zhong-Zhou Ren·Xu-Guang Huang
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Abstract

We propose to use spectator particle yield ratios to probe the configuration of $\alpha$ clusters in $^{12}$C and $^{16}$O by their collisions at RHIC and LHC energies. The idea is illustrated based on initial density distributions with various $\alpha$-cluster configurations generated by a microscopic cluster model, and without $\alpha$ clusters from mean-field calculations. The multifragmentation of the spectator matter produces more spectator light nuclei including $\alpha$ clusters in collisions of nuclei with chain structure of $\alpha$ clusters, compared to those of nuclei with a more compact structure. The yield ratio of free spectator neutrons to spectator particles with mass-to-charge ratio $A/Z=2$ scaled by their masses can be practically measured by the zero-degree calorimeter (ZDC) at RHIC and LHC, serving as a clean probe free from modeling the complicated dynamics at midrapidities.

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Lu-Meng Liu, Song-Jie Li, Zhen Wang, Jun Xu, Zhong-Zhou Ren, Xu-Guang Huang. 2023-12-21. Probing configuration of $\alpha$ clusters with spectator particles in relativistic heavy-ion collisions. https://doi.org/10.1016/j.physletb.2024.138724

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