Quasicircular inspirals and plunges from nonspinning effective-one-body Hamiltonians with gravitational self-force information

Abstract

The self-force program aims at accurately modeling relativistic two-body systems with a small mass ratio (SMR). In the context of the effective-one-body (EOB) framework, current results from this program can be used to determine the effective metric components at linear order in the mass ratio, resumming post-Newtonian (PN) dynamics around the test-particle limit in the process. It was shown in [Akcay et al., Phys. Rev. D 86 (2012)] that, in the original (standard) EOB gauge, the SMR contribution to the metric component g eff tt exhibits a coordinate singularity at the light-ring (LR) radius. In this paper, we adopt a different gauge for the EOB dynamics and obtain a Hamiltonian that is free of poles at the LR, with complete circular-orbit information at linear order in the mass ratio and non-circular-orbit and higher-order-in-mass-ratio terms up to 3PN order. We confirm the absence of the LR-divergence in such an EOB Hamiltonian via plunging trajectories through the LR radius. Moreover, we compare the binding energies and inspiral waveforms of EOB models with SMR, PN and mixed SMR-3PN information on a quasi-circular inspiral against numerical-relativity predictions. We find good agreement between NR simulations and EOB models with SMR-3PN information for both equal and unequal mass ratios. In particular, when compared to EOB inspiral waveforms with only 3PN information, EOB Hamiltonians with SMR-3PN information improves the modeling of binary systems with small mass ratios q 1/3, with a dephasing accumulated in ∼30 gravitational-wave (GW) cycles being of the order of few hundredths of a radian up to 4 GW cycles before merger.

Multipolar effective-one-body waveforms for precessing binary black holes: Construction and validation

“…14). To improve the accuracy of the models in those more challenging regions, we would need NR simulations, but also more information from analytical methods, such as the gravitational self-force [113][114][115], and resummed EOB Hamiltonians with spins [116,117].…”

“…These results demonstrate the importance of producing long NR simulations for large mass ratios and spins, which can be used to validate waveform models in this more extreme region of the parameter space. To design more accurate semi-analytical models in this particular region, it will be relevant to incorporate in the models the information from gravitational self-force [113][114][115], and also test how the choice of the underlying EOB Hamiltonians with spin effects [116,117] affects the accuracy.…”

Interpreting binary neutron star mergers: describing the binary neutron star dynamics, modelling gravitational waveforms, and analyzing detections

“…Here we are interested in specializing to static perturbations with (ξ = 0). For a barotropic EOS relation p = p(ρ) we can eliminate δ p from (32)…”

“…These choices are constrained by considerations such as a pathology-free physical behavior of quantities such as energetics of the system under variations of parameters. In addition, extra terms that parameterize unknown higher-order information are added to the model that are fixed by comparing to results from NR and gravitational self-force [31,32,[42][43][44]77].…”

Intermediate Mass-Ratio Black Hole Binaries: Applicability of Small Mass-Ratio Perturbation Theory

“…Furthermore, the application of the 1PA approximation for low frequencies is limited by a ðMΩÞ −1=3 divergence of the 2PA term. This motivates the development of models that incorporate both SMR and PN results, e.g., using effective one-body theory [73][74][75][76].…”