Comparative study of neutron and nuclear matter with simplified Argonne nucleon-nucleon potentials

We present calculations of the energy per particle of pure neutron and symmetric nuclear matter with simplified Argonne nucleon-nucleon potentials for different many-body theories. We compare critically the Brueckner-Hartree-Fock results to other formalisms, such as the Brueckner-Bethe-Goldstone expansion up to third order, self-consistent Green's functions, auxiliary field diffusion Monte Carlo, and Fermi hypernetted chain. We evaluate the importance of spin-orbit and tensor correlations in the equation of state and find these to be important in a wide range of densities.

Figure 1

$\mathit{NN}$ phase shifts for different potentials as a function of the energy in the laboratory $E_{\mathrm{lab}}$. The solid lines represent the reference Argonne $V_{18}$ results, whereas dotted, dashed, and dashed-dotted lines correspond to $V_8^{\prime }$, $V_6^{\prime }$, and $V_4^{\prime }$, respectively.

Figure 2

Energy per particle for nuclear (top panel) and neutron (bottom panel) matter as a function of density calculated in the BHF approach with the different Argonne potentials.

Figure 3

Energy per particle of SM as a function of density calculated with several many-body approaches for different Argonne potentials: $V_4^{\prime }$ (top left), $V_6^{\prime }$ (top right), $V_8^{\prime }$ (bottom left), and $V_{18}$ (bottom right).

Figure 4

Same as Fig. 3, but for NM.

Figure 5

Diagrams in the perturbation expansion of the total energy. Only direct terms are shown for simplicity.