Constraints Based on Non-detection of Kilonova Optical Searching

TL;DR

This paper develops a method to constrain neutron star equations of state by analyzing the non-detection of kilonovae in optical searches during gravitational wave events, providing new insights into neutron star properties.

Contribution

It introduces a parameter constraint technique based on non-detections, considering observational factors, and applies it to LIGO/Virgo O3 data to constrain neutron star EoS.

Findings

Constrained neutron star maximum mass to 2.17 solar masses at 90% confidence.

Placed limits on kilonova occurrence rates based on non-detections.

Outlined future prospects with the WFST telescope during O4.

Abstract

Mergers of binary neutron stars are multimessenger sources of gravitational waves that have an optical luminous counterpart, commonly referred to as 'kilonova'. Inspired by the detection of GW170817, intensive searches have been conducted during the LIGO/Virgo O3 run. However, despite these efforts, no verified kilonova was detected. In this work, we present a parameter constraint method based on non-detection of optical searching considering both GW skymap, limited sky coverage, cadence, limiting magnitudes and the probability of astrophysical origin. We use our method to place constraints on EoS of neutron star based on follow-up during O3 run and obtain $M_{\rm TOV} = 2.170^{+0.120}_{-0.108}\ M_{\odot}$ at 90\% confidence level with the combination of other observations. And we also take outlook for WFST targeting kilonova throughout the LIGO/Virgo O4 run. With more events handled, we will obtain more stringent constraints on EoS and kilonova populations.