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arXiv · 1704.02687

How tightly is nuclear symmetry energy constrained by unitary Fermi gas?

Nai-Bo Zhang·Bao-Jun Cai·Bao-An Li·William G. Newton·Jun Xu
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Abstract

We examine critically how tightly the density dependence of nuclear symmetry energy \esym is constrained by the universal equation of state (EOS) of the unitary Fermi gas $E_{\rm{UG}}(\rho)$ considering currently known uncertainties of higher order parameters describing the density dependence of the Equation of State of isospin-asymmetric nuclear matter. We found that $E_{\rm{UG}}(\rho)$ does provide a useful lower boundary for the \esym. However, it does not tightly constrain the correlation between the magnitude $E_{\rm{sym}}(\rho_0)$ and slope $L$ unless the curvature $K_{\rm{sym}}$ of the symmetry energy at saturation density $\rho_0$ is more precisely known. The large uncertainty in the skewness parameters affects the $E_{\rm{sym}}(\rho_0)$ versus $L$ correlation by the same almost as significantly as the uncertainty in $K_{\rm{sym}}$.

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Nai-Bo Zhang, Bao-Jun Cai, Bao-An Li, William G. Newton, Jun Xu. 2017-04-10. How tightly is nuclear symmetry energy constrained by unitary Fermi gas?. https://doi.org/10.1007/s41365-017-0336-2

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