Pressure Corrections to the Equation of State in the Nuclear Mean Field

Jacek Rozynek

Published 2012-05-02, updated 2013-06-21Version 4

We show the connection between stiffness of equation of state in a Relativistic Mean Field (RMF) of Nuclear Matter (NM) and the existence of a strong violation of longitudinal Momentum Sum Rule (MSR) in RMF for a finite pressure. The increasing pressure between nucleons starts to increase the ratio of nucleon Fermi to average single particle energy and according to the Hugenholtz-van Hove theorem valid for NM the MSR is broken. In order to satisfy that MSR we propose changes which modify the nucleon Parton Distribution Function (PDF) above a saturation density. The course of Equation o State in our modified RMF model is very close to semi-empirical estimation and to results obtained from extensive DBHF calculations with a Bonn A potential. Other features of the model includes a good values saturation properties including spin-orbit term. Specially the proper stiffness of EoS recently discussed in an application to compact and neutron stars is important when studying star properties (mass-radius constraint), especially the mass of "PSR J1614-2230" the most massive known neutron star, which rules out many soft equations of state including exotic matter. An admixture of additional hyperons are discussed in our approach.