2022/05/31 by Hee-Suk Cho · 17 citations
Earth and Planetary Sciences · Mathematics · Physics and Astronomy · #Astrophysics #Binary number #Distribution (mathematics) #Eccentricity (behavior) #Geometry #Geophysics and Gravity Measurements #Gravitational wave #LIGO #Mathematical analysis #Mathematics #Neutron star #Parameter space #Physics #Population #Pulsars and Gravitational Waves Research #Quantum mechanics #Seismic Imaging and Inversion Techniques #Sigma #gr-qc
paper · pdf · doi:10.1103/physrevd.105.124022
published in Physical review. D/Physical review. D. 105(12) (American Physical Society) · 16 pages, 18 figures, version published in PRD
arxiv created 2022/06/10 · openalex publication_date 2022/06/10 · arxiv updated 2022/06/13 · openalex created_date 2022/06/13 · openalex updated_date 2026/08/05
We study the impact of eccentricity on gravitational-wave parameter estimation for binary neutron star systems. For signals with small eccentricity injected into noise with the advanced LIGO power spectral density, we perform Bayesian parameter estimation using the circular waveform model and show how the recovered parameters can be biased from their true values, focusing on the intrinsic parameters the chirp mass (Mc), the symmetric mass ratio (\ensuremathη), and the tidal deformability (\stackrel\texttildelow\ensuremathλ). By comparing the results between the Bayesian and the analytic Fisher-Cutler-Vallisneri (FCV) methods, we obtain the valid criteria for the FCV approach. Employing the FCV method and using the realistic population of binary neutron star sources distributed in the m1--m2--e0 space, where e0 indicates the eccentricity at 10 Hz, we calculate the measurement errors (\ensuremathσ_\ensuremathθ) and the systematic biases (\mathrm\ensuremathΔ\ensuremathθ/\ensuremathσ_\ensuremathθ) and obtain their generalized distributions in the range of 0\ensuremath≤e0\ensuremath≤0.025. We find that for all of the three parameters, the biases increase with increasing e0, and this increase is faster for larger e0. The bias is mainly dependent on the value of e0 and weakly dependent on the component masses, and thus the distribution shows a narrow band in the e0\text\ensuremath-\mathrm\ensuremathΔ\ensuremathθ/\ensuremathσ_\ensuremathθ plane. We present various posterior examples to illustrate our new findings, such as the bimodality of posteriors. In particular, we give a specific injection-recovery example to demonstrate the importance of including eccentricity in parameter estimation to avoid incorrect predictions of the neutron star equation of state.