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arXiv · 1704.08510

A Lee-Yang--inspired functional with a density--dependent neutron-neutron scattering length

M. Grasso·D. Lacroix·C. J. Yang
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Abstract

Inspired by the low--density Lee-Yang expansion for the energy of a dilute Fermi gas of density $ρ$ and momentum $k_F$, we introduce here a Skyrme--type functional that contains only $s$-wave terms and provides, at the mean--field level, (i) a satisfactory equation of state for neutron matter from extremely low densities up to densities close to the equilibrium point, and (ii) a good--quality equation of state for symmetric matter at density scales around the saturation point. This is achieved by using a density--dependent neutron-neutron scattering length $a(ρ$) which satisfies the low--density limit (for Fermi momenta going to zero) and has a density dependence tuned in such a way that the low--density constraint $|a(ρ) k_F| \le 1$ is satisfied at all density scales.

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M. Grasso, D. Lacroix, C. J. Yang. 2017-04-27. A Lee-Yang--inspired functional with a density--dependent neutron-neutron scattering length. https://doi.org/10.1103/physrevc.95.054327

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