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arXiv · 2205.11010

Spinodal Enhancement of Light Nuclei Yield Ratio in Relativistic Heavy Ion Collisions

Kai-Jia Sun·Wen-Hao Zhou·Lie-Wen Chen·Che Ming Ko·Feng Li·Rui Wang·Jun Xu
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Abstract

Using a relativistic transport model to describe the evolution of the quantum chromodynamic matter produced in Au+Au collisions at $\sqrt{s_{NN}}=3-200$ GeV, we study the effect of a first-order phase transition in the equation of state of this matter on the yield ratio $N_tN_p/ N_d^2$ ($tp/d^2$) of produced proton ($p$), deuteron ($d$), and triton ($t$). We find that the large density inhomogeneities generated by the spinodal instability during the first-order phase transition can survive the fast expansion of the subsequent hadronic matter and lead to an enhanced $tp/d^2$ in central collisions at $\sqrt{s_{NN}}=3-5$ GeV as seen in the experiments by the STAR Collaboration and the E864 Collaboration. However, this enhancement subsides with increasing collision centrality, and the resulting almost flat centrality dependence of $tp/d^2$ at $\sqrt{s_{NN}}=3$ GeV can also be used as a signal for the first-order phase transition.

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Kai-Jia Sun, Wen-Hao Zhou, Lie-Wen Chen, Che Ming Ko, Feng Li, Rui Wang, Jun Xu. 2022-05-23. Spinodal Enhancement of Light Nuclei Yield Ratio in Relativistic Heavy Ion Collisions. https://arxiv.org/abs/2205.11010

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