Basic Parameter Estimation of Binary Neutron Star Systems by the Advanced LIGO/Virgo Network

TL;DR

This paper evaluates the precision of parameter estimation for binary neutron star mergers using the Advanced LIGO/Virgo network, employing full Bayesian methods to improve upon previous approximation-based studies.

Contribution

It provides detailed statistical uncertainties for key parameters of neutron star mergers using Markov-Chain Monte Carlo, advancing the understanding of expected measurement accuracy.

Findings

Mass recovery within 9-15% for equal-mass systems

Sky localization uncertainty median of 5.1 deg^2

Addition of LIGO India improves localization to 2.3 deg^2

Abstract

Within the next five years, it is expected that the Advanced LIGO/Virgo network will have reached a sensitivity sufficient to enable the routine detection of gravitational waves. Beyond the initial detection, the scientific promise of these instruments relies on the effectiveness of our physical parameter estimation capabilities. The majority of this effort has been towards the detection and characterization of gravitational waves from compact binary coalescence, e.g. the coalescence of binary neutron stars. While several previous studies have investigated the accuracy of parameter estimation with advanced detectors, the majority have relied on approximation techniques such as the Fisher Matrix. Here we report the statistical uncertainties that will be achievable for optimal detection candidates (SNR = 20) using the full parameter estimation machinery developed by the LIGO/Virgo Collaboration via Markov-Chain Monte Carlo methods. We find the recovery of the individual masses to be fractionally within 9% (15%) at the 68% (95%) credible intervals for equal-mass systems, and within 1.9% (3.7%) for unequal-mass systems. We also find that the Advanced LIGO/Virgo network will constrain the locations of binary neutron star mergers to a median uncertainty of 5.1 deg^2 (13.5 deg^2) on the sky. This region is improved to 2.3 deg^2 (6 deg^2) with the addition of the proposed LIGO India detector to the network. We also report the average uncertainties on the luminosity distances and orbital inclinations of ideal detection candidates that can be achieved by different network configurations.