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arXiv · 1006.4321

Nuclear symmetry energy and its density slope at normal density extracted from global nucleon optical potentials

Chang Xu·Bao-An Li·Lie-Wen Chen
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Abstract

Based on the Hugenholtz-Van Hove theorem, it is shown that both the symmetry energy E$_{sym}(ρ)$ and its density slope $L(ρ)$ at normal density $ρ_0$ are completely determined by the global nucleon optical potentials that can be extracted directly from nucleon-nucleus scatterings, (p,n) charge exchange reactions and single-particle energy levels of bound states. Adopting a value of $m^*/m=0.7$ for the nucleon effective k-mass in symmetric nuclear matter at $ρ_0$ and averaging all phenomenological isovector nucleon potentials constrained by world data available in the literature since 1969, the best estimates of $E_{sym}(ρ_0)=31.3$ MeV and $L(ρ_0)=52.7$ MeV are simultaneously obtained. Uncertainties involved in the estimates are discussed.

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Chang Xu, Bao-An Li, Lie-Wen Chen. 2010-06-22. Nuclear symmetry energy and its density slope at normal density extracted from global nucleon optical potentials. https://doi.org/10.1103/physrevc.82.054607

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