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arXiv · 2001.01892

The roles of individual advanced LIGO detectors on revealing the neutron star properties

Abstract

In this work we re-analyze the data of GW170817, the first binary neutron star (BNS) merger event, in two ways, including the parameterized equation of state (EoS) method and gravitational wave (GW) parameter estimation analysis. Three sets of data, including the combined LIGO/Virgo (HLV) data, the LIGO-Hanford (H1) data and the LIGO-Livingston (L1) data, have been analyzed, respectively. We confirm the bimodal probability distribution of the tidal deformability of GW170817 with the HLV data and resolve the different contributions of H1 and L1 detectors. Our simulation reveals a tendency of ``overestimating" the tidal parameter with the decreasing signal-to-noise ratio (SNR). Such a tendency is likely caused by the dependence of the result on the prior (which is not well understood and has been assumed to be widely-distributed) in the low SNR case. Though this effect is interesting, the slightly higher SNR of H1 than L1 at frequencies above $\sim 100$ Hz is most-likely not the main reason for the lower tidal parameter region favored by H1. In view of the large fluctuation of the expected tide parameter in the case of low SNR, the different probability distributions favored by the L1 and H1 data of GW170817 are reasonable. We have also explored the dependence of expected difference of SNRs of H1 and L1 detectors on the source locations in the O3 and full sensitivity runs. Such maps are helpful in evaluating the relative powers of individual detectors on measuring the tidal deformabilities for the new double neutron star merger events.

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Ming-zhe Han, Jin-liang Jiang, Shao-peng Tang, Yin-jie Li, Yi-zhong Fan. 2020-01-07. The roles of individual advanced LIGO detectors on revealing the neutron star properties. https://arxiv.org/abs/2001.01892

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