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arXiv · 0711.0118

Density dependence of the "symmetry energy" in the lattice gas model

Q. M. Su·Y. G. Ma·W. D. Tian·D. Q. Fang·X. Z. Cai·K. Wang
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Abstract

Isoscaling behavior of the statistical emission fragments from the equilibrated sources with $Z$ = 30 and $N$ = 30, 33, 36 and 39, resepectively, is investigated in the framework of isospin dependent lattice gas model. The dependences of isoscaling parameters $α$ on source isospin asymmetry, temperature and freeze-out density are studied and the "symmetry energy" is deduced from isoscaling parameters. Results show that "symmetry energy" $C_{sym}$ is insensitive to the change of temperature but follows the power-law dependence on the freeze-out density $ρ$. The later gives $C_{sym}$ = 30$(ρ/ρ_0)^{0.62}$ if the suitable asymmetric nucleon-nucleon potential is taken. The effect of strength of asymmetry of nucleon-nucleon interaction potential on the density dependence of the "symmetry energy" is dicussed.

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Q. M. Su, Y. G. Ma, W. D. Tian, D. Q. Fang, X. Z. Cai, K. Wang. 2007-11-01. Density dependence of the "symmetry energy" in the lattice gas model. https://doi.org/10.1088/0256-307x%2F25%2F6%2F021

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