Estimation of the MTOV precision for ET, CE, and NEMO from the post-merger of BNS coalescences

TL;DR

This paper assesses how accurately next-generation gravitational wave detectors can estimate the maximum non-rotating neutron star mass (MTOV) from post-merger signals, highlighting current limitations and the need for improved high-frequency sensitivity.

Contribution

It provides a quantitative analysis of MTOV estimation precision from post-merger signals for ET, CE, and NEMO, emphasizing the importance of detector sensitivity improvements.

Findings

CE can achieve a mass precision of 0.3-0.8 M_sun under optimistic conditions

Precision depends on the final remnant mass and SNR

Enhanced high-frequency sensitivity is necessary for better MTOV estimates

Abstract

The detection of the gravitational waves produced after the coalescence of two neutron stars is greatly anticipated because it will be able to provide information about matter in extreme conditions, especially if the remnant turns out to go through a hypermassive or a supermassive neutron star state before collapsing into a black hole. Next-generation gravitational wave detectors such as ET, CE, and NEMO are expected to observe high-frequency gravitational wave signals, that is, the post-merger stage of the coalescence of binary neutron stars; then from these signals one can estimate the maximum mass that a spinless neutron star (MTOV ) can have. In this paper, we investigate the problem of the determination of the MTOV precision from the post-merger detected by next-generation observatories. Our results show that only under the most optimistic scenario of signal-to-noise ratio for post-merger signals ($\mathrm{SNR}\geq 8$) and merger rate density (250Gpc-3yr-1), CE achieves marginally a mass precision in the range $\delta M/2 \approx 0.3-0.8\,M_{\odot}$ for a remnant mass of $2.57\,M_{\odot}$. We clarify that this precision represents the minimum uncertainty, corresponding to the most probable value (main peak) in the final mass distribution, showing that it depends on the value of the final (remnant) mass. Therefore, based on the results obtained in this study, it will still be necessary to improve the sensitivity at high frequencies of future ground-based gravitational wave observatories if one wants to obtain greater precision in the MTOV estimation. One possibility would be to improve the sensitivity in a frequency range that allows us to determine whether or not a black hole was formed in the coalescence.