Limitations in constraining neutron star radii and nuclear properties from inspiral gravitational wave detections

ORAL

Abstract

We investigate the constraints on the neutron star equation of state (EoS) and nuclear properties achievable

with third-generation gravitational wave detectors using the Fisher information matrix approach. Assuming an

optimistic binary neutron star (BNS) merger rate, we generate synthetic inspiral gravitational wave (GW) signals

corresponding to one year of observation. From these simulated data, we compute the covariance matrix and

posterior distributions for nuclear properties and EoS. Our results show that the EoS can be tightly constrained,

particularly in the density range between one and four times nuclear saturation density. However, due to the

scarcity of of low-mass neutron stars in the GW sample, the EoS at sub-saturation densities remains poorly

constrained. Thus, in turn, leads to weaker constraints on neutron star radii, as the radii are sensitive to the

low-density EoS. Additionally, We note that the nuclear properties are degenerate in their influence on the EoS,

making them difficult to be constrained through GW observations alone. These highlights inherent limitations of

inspiral GW signals in probing dense matter properties. Therefore, precise radius measurements, post-merger

GW observations, and supplementary constraints from terrestrial nuclear experiments remain essential for a

comprehensive understanding of dense matter.

*We acknowledges support from NSF AAG 2206321 and NSF PHY 2309172 and 2207920. The authors are grateful for computational resources provided by the LIGO Laboratory and supported by National Science Foundation Grants PHY-0757058 and PHY-0823459.

Publication: https://arxiv.org/abs/2508.11875

Presenters

  • Zhenyu Zhu

    • Rochester Institute of Technology

Authors

  • Zhenyu Zhu

    • Rochester Institute of Technology
  • Richard O’Shaughnessy

    • Rochester Institute of Technology