centra

Speaker: Kaushik Paul (Indian Institute of Technology Madras)

Title: Modeling spin and eccentricity effects in compact binary mergers

Abstract: With the improved sensitivity of ground-based interferometric gravitational wave detectors in their fourth observing run, we expect higher detection rates of compact binary mergers. With this comes the hope that we shall also detect rarer classes of such events. Compact binaries formed dynamically in dense stellar environments are likely to be detected with a residual eccentricity as they enter the sensitivity band of ground-based gravitational wave detectors. Further, black holes in compact binaries are also expected to have significant spins that modify the shape and size of the waveform. Ignoring these effects in waveforms may reduce the detection efficiency and lead to a biased estimation of binary parameters. In this presentation, I shall discuss the modelling of spinning compact binaries on eccentric orbits in detail. There are two parts to the presentation — in the first part, the computation of the linear and quadratic order spin effects in spherical harmonic modes of gravitational waveforms through the second post-Newtonian order (2PN) from inspiralling compact binaries in noncircular orbits with component spins aligned to orbital angular momentum vector computed within multipolar-post-minkowskian-post-Newtonian formalism (MPM-PN) will be discussed. The results are reported in Kaushik Paul et al., Physical Review D 108, 024023 (2023). In the second part of the talk, I shall discuss the implementation of the above model into a numerical framework we call ESIGMA. The final version of the model is presented in Kaushik Paul et al., arXiv:2409.13866. The model was validated against eccentric Numerical Relativity simulations and also against contemporary effective-one-body and phenomenological models in the quasi-circular limit. Further, the model is used to show that current templated LIGO-Virgo-KAGRA searches will lose more than 10% of optimal signal-to-noise ratio (SNR) for about 20% of all eccentric sources if eccentricity is neglected when performing searches.