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arXiv · 2211.03297

Neutron density fluctuation and neutron-proton correlation from AMPT model

Zuman Zhang·Ning Yu·Hongge Xu
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Abstract

Using the multiphase transport (AMPT) model, we study the relative neutron density fluctuation and neutron-proton correlation in matter produced by Au+Au collisions at $\sqrt{s_\text{NN}} = $7.7-200 GeV. The rapidity, centrality, and energy dependence of these two observations are also discussed. The light nuclei yield ratio of proton, deuteron, and triton $N_tN_p/N_d^2$ calculated directly from the relative neutron density fluctuation and neutron-proton correlation, decreases with rapidity coverage and increases with collision centrality. Our study also found that the ratio does not exhibit any non-monotonic behavior in collision energy dependence. Since there is no first-order phase transition or critical physics in the AMPT model, our work provides a reference for extracting the relative neutron density fluctuation from light nuclei production in experiments.

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Zuman Zhang, Ning Yu, Hongge Xu. 2022-11-07. Neutron density fluctuation and neutron-proton correlation from AMPT model. https://doi.org/10.1140/epja%2Fs10050-022-00897-2

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