are performed at zero temperature.

The TW density dependent hadronic model
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Next we describe the main quantities of the TW model, which has density dependent coupling parameters. The Lagrangian density reads: $${\cal L}=\bar \psi\left[\gamma_\mu\left(i\partial^{\mu}-\Gamma_v V^{\mu}-
\frac{\Gamma_{\rho}}{2}  \boldsymbol{\tau} \cdot \mathbf {b}^\mu \right. \right.$$ $$\left. \left. -e  \frac{(1+\tau_{i3})}{2} A^\mu \right)
-(M-\Gamma_s \phi)\right]\psi$$ $$+\frac{1}{2}(\partial_{\mu}\phi\partial^{\mu}\phi
-m_s^2 \phi^2)
-\frac{1}{4}\Omega_{\mu\nu}\Omega^{\mu\nu}$$ $$+\frac{1}{2}m_v^2 V_{\mu}V^{\mu}
-\frac{1}{4}\mathbf B_{\mu\nu}\cdot\mathbf B^{\mu\nu}+\frac{1}{2}
m_\rho^2 \mathbf b_{\mu}\cdot \mathbf b^{\mu}
-\frac{1}{4}F_{\mu\nu}F^{\mu\nu}
\label{lagtw}$$ where $\phi$, $V^\mu$, $\mathbf {b}^\mu$ and $A^{\mu}$ are the scalar-isoscalar, vector-isoscalar and vector-isovector meson fields and the photon field respectively, $\Omega_{\mu\nu}=\partial_{\mu}V_{\nu}-\partial_{\nu}V_{\mu}$ , $\mathbf B_{\mu\nu}=\partial_{\mu}\mathbf b_{\nu}-\partial_{\nu} \mathbf b_{\mu}
- \Gamma_\rho (\mathbf b_\mu \times \mathbf b_\nu)$, $F_{\mu\nu}=\partial_{\mu}A_{\nu}-\partial_{\nu}A_{\mu}$ and $\tau_{p3}=1$, and $\tau_{n3}=-1$. The parameters of the model are: the nucleon mass $M=939$ MeV, the masses of the mesons $m_s$, $m_v$, $m_\rho$, the electromagnetic coupling constant $e=\sqrt{4\pi/137}$ and the density dependent coupling constants $\Gamma_{s}$, $\Gamma_v$ and $\Gamma_{\rho}$, which are adjusted in order to reproduce some of the nuclear matter bulk properties shown in Table \[bulk\], using the following parametrization: $$\Gamma _{i}(\rho )=\Gamma _{i}(\rho _{sat})h_{i}(x),\quad x=\rho /\rho _{sat},
\label{paratw1}$$ with $$h_{i}(x)=a_{i}\frac{1+b_{i}(x+d_{i})^{2}}{1+c_{i}(x+d_{i})^{2}},\quad i=s,v$$ and $$h_{\rho }(x)=\exp [-a_{\rho }(x-1)],  \label{paratw2}$$ with the values of the parameters $m_{i}$, $\Gamma _{i}(\rho_{sat})$, $a_{i}$, $b_{i}$, $c_{i}$ and $d_{i}$, $i=s,v,\rho $ given in [@tw]. This 