Equation of State for Nucleonic Matter and its Quark Mass Dependence from the Nuclear Force in Lattice QCD

TL;DR

This study derives the equation of state for nucleonic matter from lattice QCD simulations, examining how it varies with quark mass and implications for neutron star properties.

Contribution

It provides the first lattice QCD-based EOS for nucleonic matter, exploring quark mass dependence and neutron star implications.

Findings

Nuclear matter saturates at a quark mass corresponding to a pseudoscalar meson mass of ~469 MeV.

The EOS becomes stiffer as quark mass decreases, increasing the maximum neutron star mass.

Neutron star mass-radius relations are consistent with observational constraints.

Abstract

Quark mass dependence of the equation of state (EOS) for nucleonic matter is investigated, on the basis of the Brueckner-Hartree-Fock method with the nucleon-nucleon interaction extracted from lattice QCD simulations. We observe saturation of nuclear matter at the lightest available quark mass corresponding to the pseudoscalar meson mass ~ 469 MeV. Mass-radius relation of the neutron stars is also studied with the EOS for neutron-star matter from the same nuclear force in lattice QCD. We observe that the EOS becomes stiffer and thus the maximum mass of neutron star increases as the quark mass decreases toward the physical point.