Exploring tidal effects of coalescing binary neutron stars in numerical relativity II: Longterm simulations

Abstract

We perform new longterm (15-16 orbits) simulations of coalescing binary neutron stars in numerical relativity using an updated Einstein's equation solver, employing low-eccentricity initial data, and modeling the neutron stars by a piecewise polytropic equation of state. A convergence study shows that our new results converge more rapidly than the third order and using the determined convergence order, we construct an extrapolated waveform for which the estimated total phase error should be less than 1 radian. We then compare the extrapolated waveforms with those calculated by the latest effective-one-body (EOB) formalism in which the so-called tidal deformability, higher post-Newtonian corrections, and gravitational self-force effects are taken into account. We show that for a binary of compact neutron stars with their radius 11.1 km, the waveform by the EOB formalism agrees quite well with the numerical waveform so that the total phase error is smaller than 1 radian for the total phase of $\sim 200$ radian up to the merger. By contrast, for a binary of less compact neutron stars with their radius 13.6 km, the EOB and numerical waveforms disagree with each other in the last few wave cycles, resulting in the total phase error of $\sim 3$ radian.

12 pages, 4 figures, submitted to PRD

References in corpus (12)

• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• Constraining neutron star tidal Love numbers with gravitational wave detectors
• Constraints on a phenomenologically parameterized neutron-star equation of state
• Calibration of Moving Puncture Simulations
• Simulating coalescing compact binaries by a new code SACRA
• Tidal effects in binary neutron star coalescence
• Improved effective-one-body description of coalescing nonspinning black-hole binaries and its numerical-relativity completion
• Calibration of the LIGO Gravitational Wave Detectors in the Fifth Science Run
• Gravitational self-force corrections to two-body tidal interactions and the effective one-body formalism
• Calibration and sensitivity of the Virgo detector during its second science run
• Intermediate-mass-ratio black hole binaries: intertwining numerical and perturbative techniques

Cited by in corpus (1)

• Linear-in-mass-ratio contribution to spin precession and tidal invariants in Schwarzschild spacetime at very high post-Newtonian order