Massive Neutron Stars with Antikaon Condensates in a Density Dependent Hadron Field Theory

TL;DR

This paper explores how antikaon condensates and hyperons affect the equation of state and maximum mass of neutron stars, aiming to explain observations of neutron stars with masses around 2 solar masses.

Contribution

It introduces a density-dependent relativistic mean field model incorporating antikaon condensates and hyperons to study neutron star properties.

Findings

Antikaon condensates can support neutron stars with masses up to 2 solar masses.

Hyperons influence the stiffness of the equation of state at high densities.

The model aligns with observational constraints on neutron star masses.

Abstract

The measurement of $1.97 \pm 0.04 M_{solar}$ for PSR J1614-2230 and $2.01 \pm 0.04M_{solar}$ for PSR J0348+0432 puts a strong constraint on the neutron star equation of state and its exotic composition at higher densities. In this paper, we investigate the possibility of exotic equation of state within the observational mass constraint of $2M_{solar}$ in the framework of relativistic mean field model with density-dependent couplings. We particularly study the effect of antikaon condensates in the presence of hyperons on the mass-radius relationship of the neutron star.