Neutron matter within QCD sum rules

TL;DR

This paper uses QCD sum rules to analyze the equation of state of pure neutron matter, showing the importance of higher-order density terms in quark condensates for accurate modeling at high densities.

Contribution

It demonstrates the significance of higher-order density terms in quark condensates within QCD sum rules for describing neutron matter at suprasaturation densities, a novel insight.

Findings

QCDSR results agree with microscopic many-body theories

Higher-order density terms are crucial at high densities

These terms hinder chiral symmetry restoration at high densities

Abstract

Equation of state (EOS) of pure neutron matter (PNM) is studied in QCD sum rules (QCDSR). It is found that the QCDSR results on EOS of PNM are in good agreement with predictions by current advanced microscopic many-body theories. Moreover, the higher-order density terms in quark condensates are shown to be important to describe the empirical EOS of PNM in the density region around and above nuclear saturation density although they play minor role at subsaturation densities. The chiral condensates in PNM are also studied, and our results indicate that the higher-order density terms in quark condensates, which are introduced to reasonably describe the empirical EOS of PNM at suprasaturation densities, tend to hinder the appearance of chiral symmetry restoration in PNM at high densities.