Eur. Phys. J. A (2019) 55: 34
https://doi.org/10.1140/epja/i2019-12713-7

Regular Article - Theoretical Physics

Equilibrium of nuclear matter in QCD sum rules

National Research Center “Kurchatov Institute”, B. P. Konstantinov Petersburg Nuclear Physics Institute, 188300, Gatchina, St. Petersburg, Russia

^* e-mail: drukarev@thd.pnpi.spb.ru

Received: 29 May 2018
Accepted: 29 January 2019
Published online: 12 March 2019

Abstract

We calculate the nucleon parameters in symmetric nuclear matter employing the QCD sum rules approach. We focus on the average energy per nucleon and study the equilibrium states of the matter. We treat the matter as a relativistic system of interacting nucleons. Assuming the dependence of the nucleon mass on the light quark mass to be more important than that of nucleon interactions we find that the contribution of the relativistic nucleons to the scalar quark condensate can be expressed as that caused by the nucleon matrix element multiplied by the density dependent factor caused by the relativistic motion of nucleons composing the matter. We demonstrate that there are no equilibrium states while we include only the condensates with dimension . There are equilibrium states if we include the lowest order radiative corrections and the condensates with . They manifest themselves for the nucleon sigma term MeV. Including the condensates with we find equilibrium states of nuclear matter for MeV. In all cases the equilibrium states are due to influence of the relativistic motion of nucleons on the scalar quark condensate.