Early Advanced LIGO binary neutron-star sky localization and parameter estimation

TL;DR

This paper evaluates the early capabilities of Advanced LIGO in localizing and estimating parameters of binary neutron-star mergers, highlighting rapid sky localization but large positional uncertainties and mass measurement challenges.

Contribution

It provides the first simulation-based assessment of BNS parameter estimation and sky localization accuracy in the early advanced-detector era.

Findings

Sky localization can be achieved in about 5 seconds.

Sky areas for localization may span hundreds of square degrees.

Chirp mass is measured with high precision (better than 0.1%).

Abstract

2015 will see the first observations of Advanced LIGO and the start of the gravitational-wave (GW) advanced-detector era. One of the most promising sources for ground-based GW detectors are binary neutron-star (BNS) coalescences. In order to use any detections for astrophysics, we must understand the capabilities of our parameter-estimation analysis. By simulating the GWs from an astrophysically motivated population of BNSs, we examine the accuracy of parameter inferences in the early advanced-detector era. We find that sky location, which is important for electromagnetic follow-up, can be determined rapidly (~5 s), but that sky areas may be hundreds of square degrees. The degeneracy between component mass and spin means there is significant uncertainty for measurements of the individual masses and spins; however, the chirp mass is well measured (typically better than 0.1%).