Role of Hyperons in Neutron Stars

TL;DR

This paper discusses how the presence of hyperons in neutron star matter aligns with recent observations of massive pulsars, challenging previous assumptions that non-nucleonic components are unlikely.

Contribution

It demonstrates that hyperons are compatible with observational constraints and are a necessary aspect of high-density neutron star matter.

Findings

Hyperons can exist in neutron star cores without contradicting mass measurements.

The presence of hyperons is consistent with recent pulsar mass observations.

Hyperons are a necessary consequence of fundamental physical laws in dense matter.

Abstract

The latest observation of a Shapiro delay of the binary millisecond pulsar J1614-2230 by Demorest et al. Nature 467 1081 (2010) yielded the pulsar gravitational mass to be 1.97 +/- 0.04 solar mass, the heaviest observed pulsar to-date. This result produces a stringent constraint on Equation(s) of State (EoS) of high density neutron star matter. One of the main conclusions of Demorest et al. was that their result makes the presence of non-nucleonic components in the neutron star matter unlikely. We compare the result with our recent work and conclude that hyperons in high-density matter are fully consistent with the observation and that their presence is a necessary consequence of general physical laws.