Quentin Henry and Anna Heffernan, researchers from the University of Cambridge, have recently published a study that delves into the dynamics of compact binaries on quasi-elliptic orbits, a topic of growing interest in the field of gravitational wave astronomy. Their work, titled “Adiabatic tides in compact binaries on quasi-elliptic orbits: Dynamics at the second-and-a-half relative post-Newtonian order,” was published in the journal Physical Review D.
The study focuses on the detection of GW200105, a gravitational wave event that marked the first observation of a neutron star-black hole binary with signs of eccentricity. This discovery underscores the need for more accurate waveforms that can incorporate tidal effects on quasi-elliptic orbits. The researchers tackle this challenge by examining finite size effects within the post-Newtonian framework, which is a method used to approximate solutions to the Einstein field equations for binary systems.
Henry and Heffernan’s work involves a detailed analysis of the mass-type quadrupole and octupole, as well as the current-type quadrupole deformations in the adiabatic approximation. They perform these computations at the second-and-a-half relative post-Newtonian order, a level of approximation that provides a more precise understanding of the dynamics involved. The researchers derive the quasi-Keplerian parametrization of the conservative motion, expressing the radial separation and phase with their time derivatives in terms of the orbital frequency, the time eccentricity, and the eccentric anomaly.
One of the key contributions of this study is the inversion of the generalized Kepler equation to obtain the time derivatives as functions of time. The researchers discuss the convergence of eccentricity expanded results and provide these results to the fourteenth order in eccentricity. Additionally, they exploit the known radiation reaction term of the acceleration to derive the secular and oscillatory evolutions of the orbital elements.
The companion paper to this study contains the derivation of the radiated fluxes and the amplitude modes of the strain. All relevant results are provided in an ancillary file, making the findings accessible for further research and application. This work is crucial for improving the accuracy of gravitational wave detectors and enhancing our understanding of compact binary systems, which has significant implications for the energy sector, particularly in the development of advanced energy technologies that rely on precise measurements and theoretical models.
Source: Henry, Quentin, and Anna Heffernan. “Adiabatic tides in compact binaries on quasi-elliptic orbits: Dynamics at the second-and-a-half relative post-Newtonian order.” Physical Review D.
This article is based on research available at arXiv.