Including mode mixing in a higher-multipole model for gravitational waveforms from nonspinning black-hole binaries
As gravitational-wave (GW) observations of binary black holes are becoming a precision tool for physics and astronomy, several subdominant effects in the GW signals need to be accurately modeled. Previous studies have shown that neglecting subdominant modes in the GW templates causes an unacceptable loss in detection efficiency and large systematic errors in the estimated parameters for binaries with large mass ratios. Our recent work [Mehta et al., Phys. Rev. D 96, 124010 (2017)] constructed a phenomenological gravitational waveform family for nonspinning black-hole binaries that includes subdominant spherical harmonic modes (ℓ=2, m=±1), (ℓ=3, m=±3), and (ℓ=4, m=±4) in addition to the dominant quadrupole mode, (ℓ=2, m=±2). In this article, we construct analytical models for the (ℓ=3, m=±2) and (ℓ=4, m= ±3) modes and include them in the existing waveform family. Accurate modeling of these modes is complicated by the mixing of multiple spheroidal harmonic modes. We develop a method for accurately modeling the effect of mode mixing, thus producing an analytical waveform family that has faithfulness greater than 99.6%.
© 2019 American Physical Society. Received 15 February 2019; published 16 July 2019. We are grateful to the SXS Collaboration for making a public catalog of numerical-relativity waveforms. We also thank Emanuele Berti and Michael Boyle for useful discussions and clarifications, Frank Ohme for helpful comments, and Mark Scheel for providing a Cauchy-characteristic extraction SXS waveform for comparison. A. K.M., P. A., and V. V. acknowledge support from the Indo-US Centre for the Exploration of Extreme Gravity funded by the Indo-US Science and Technology Forum (Grant No. IUSSTF/JC-029/2016). N. K. J.-M. acknowledges support from the AIRBUS GroupCorporate Foundation through a chair in "Mathematics of Complex Systems" at the International Centre for Theoretical Sciences (ICTS) and from STFC Consolidator Grant No. ST/L000636/1. Also, this work has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant No. 690904. P. A.'s research was supported by the Max Planck Society through a Max Planck Partner Group at ICTS-TIFR and by the Canadian Institute for Advanced Research through the CIFAR Azrieli Global Scholars program. V. V.'s research was supported by the Sherman Fairchild Foundation, and NSF Grants No. PHY–170212 and No.PHY–1708213 at Caltech.Computations were performed at the ICTS cluster Alice. This document has LIGO preprint number LIGO-P1800203-v6.
Accepted Version - 1902.02731.pdf
Published - PhysRevD.100.024032.pdf