Eur. Phys. J. A (2015) 51: 98
https://doi.org/10.1140/epja/i2015-15098-7

Regular Article - Theoretical Physics

Nuclear and neutron matters at low density

Physics Department, Faculty of Science, Sohag University, Sohag, Egypt

^* e-mail: khalafgad@yahoo.com

Received: 21 April 2015
Revised: 19 July 2015
Accepted: 27 July 2015
Published online: 13 August 2015

Abstract

In this study, symmetric and asymmetric nuclear matter, as well as pure neutron matter in the low-density regime, where the density ranges 0.01 fm⁻³ ρ 0.13 fm⁻³, have been investigated. Two different realistic and accurate two-body forces are considered. These include Argonne V18 and the CD-Bonn, which give quite different equations of state. The binding energy per nucleon as a function of the density is calculated using the Brueckner-Hartree-Fock approximation. Both the conventional (gap) and continuous choice of single-particle energies are utilized. For the sake of comparison, the equation of state within the self-consistent Green’s function approach is calculated using the CD-Bonn potential. The contribution of the hole-hole terms leads to a repulsive contribution to the energy per nucleon which increases with the nuclear density. Significantly, very good agreement between the experimental symmetry energy values and those calculated in the self-consistent Green’s function and BHF approaches especially at low density, has been accomplished. Finally, The results are compared with those from various many-body approaches, such as variational and relativistic mean field approaches.