Nuclear equation of state and finite nucleon volumes
It is shown how the equation of state (EoS) depends on nucleon properties inside nuclear matter (NM). We propose to benefit from the concept of enthalpy in order to include volume corrections to the nucleon rest energy, which are proportional to pressure and absent in a standard relativistic mean field (RMF) with point-like nucleons. As a result, the nucleon mass can decrease inside NM, making the model nonlinear and the EoS softer. The course of the EoS in our RMF model agrees with a semi-empirical estimate and is close to the results obtained from extensive DBHF calculations with a Bonn A potential, which produce an EoS stiff enough to describe neutron star properties (mass–radius constraint), especially the masses of ‘PSR J16142230’ and ‘PSR J0348 + 0432’, known as the most massive () neutron stars. The presented model has proper saturation properties, including a good value of compressibility.