Pressure of Pure Neutron Matter and BHFA

Abstract

This study investigates the pressure of pure neutron matter using the Brueckner–Hartree–Fock Approximation (BHFA), taking into account the effects of three-body forces among nucleons through the introduction of a density-dependent two-body Skyrme-type interaction. The nucleon–nucleon interaction potential of the Nijmegen 1 (Nijm1) type was adopted within the framework of the Brueckner–Hartree–Fock approach to calculate the equation of state and the pressure of pure neutron matter. The theoretical calculations were performed at different temperatures, namely
T=0T = 0, 88, and 1212 MeV, in order to investigate the effect of temperature on the pressure behavior as a function of matter density. The obtained results were compared with previous calculations by Baldo and Ferreira using the realistic interaction potential (v14+TNI). The results showed good agreement with previous theoretical predictions, particularly in the low-density region, confirming the capability of the BHFA method, supplemented by an equivalent three-body force correction, to describe the pressure behavior of pure neutron matter satisfactorily. The results indicate that the adopted model provides an appropriate representation of the thermal and mechanical properties of neutron matter within the studied density range, making it a suitable approach for theoretical investigations related to dense nuclear matter physics and the internal structure of neutron stars.