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$Σ^-/Σ^+$ ratio as a candidate for probing the density dependence of the symmetry potential at high nuclear densities

Qingfeng LI·Zhuxia LI·Enguang Zhao·Raj K. Gupta
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Abstract

Based on the UrQMD model, we have investigated the influence of the symmetry potential on the negatively and positively charged $π$ and $Σ$ hyperon production ratios in heavy ion collisions at the SIS energies. We find that, in addition to $π^-/π^+$ ratio, the $Σ^-/Σ^+$ ratio can be taken as a sensitive probe for investigating the density dependence of the symmetry potential of nuclear matter at high densities (1-4 times of normal baryon density). This sensitivity of the symmetry potential to both the $π^-/π^+$ and $Σ^-/Σ^+$ ratios is found to depend strongly on the incident beam energy. Furthermore, the $Σ^-/Σ^+$ ratio is shown to carry the information about the isospin-dependent part of the $Σ$ hyperon single-particle potential.

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Qingfeng LI, Zhuxia LI, Enguang Zhao, Raj K. Gupta. 2005-04-22. $Σ^-/Σ^+$ ratio as a candidate for probing the density dependence of the symmetry potential at high nuclear densities. https://doi.org/10.1103/physrevc.71.054907

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