Correlations between the nuclear matter symmetry energy, its slope, and curvature from a nonrelativistic solvable approach and beyond

By using point-coupling versions of finite range nuclear relativistic mean field models containing cubic and quartic self interactions in the scalar field $\sigma$, a nonrelativistic limit is achieved. This approach allows an analytical expression for the symmetry energy ($J$) as a function of its slope ($L$) in a unified form, namely, $L=3J+f(m^{\ast },{\rho }_o,B_o,K_o)$, where the quantities $m^{\ast }$, ${\rho }_o$, $B_o$ and $K_o$ are bulk parameters at the nuclear matter saturation density ${\rho }_o$. This result establishes a linear correlation between $L$ and $J$ which is reinforced by exact relativistic calculations. An analogous analytical correlation is also found for $J$, $L$ and the symmetry energy curvature ($K_{sym}$). Based on these results, we propose graphic constraints in $L\times J$ and $K_{sym}\times L$ planes which finite range models must satisfy.