Anatomy of a slow merger: dissecting secularly-driven inspirals of LIGO/Virgo gravitational wave sources

Abstract

The dozens of compact object mergers detected by LIGO/Virgo raise a key theoretical question: how do initially wide binaries shrink sufficiently quickly that they are able to merge via gravitational wave (GW) radiation within a Hubble time? One promising class of answers involves secular driving of binary eccentricity by some external tidal perturbation. This perturbation can arise due to the presence of a tertiary point mass, in which case the system exhibits Lidov-Kozai (LK) dynamics, or it can stem from the tidal field of the stellar cluster in which the binary orbits. While these secular tide-driven mechanisms have been studied exhaustively in the case of no GW emission, when GWs are included the dynamical behavior is still incompletely understood. In this paper we consider compact object binaries driven to merger via high eccentricity excitation by (doubly-averaged, test-particle quadrupole level) cluster tides - which includes LK-driven mergers as a special case - and include the effects of both general relativistic precession and GW emission. We provide for the first time an analytical understanding of the different evolutionary stages of the binary's semimajor axis, secular oscillation timescale, and phase space structure all the way to merger. Our results will inform future population synthesis calculations of compact object binary mergers from hierarchical triples and stellar clusters.

arXiv comment30 pages, 12 figures. To be submitted to ApJ. Comments welcome

References in corpus (25)

• Shrinking binary and planetary orbits by Kozai cycles with tidal friction
• The Eccentric Kozai-Lidov Effect and Its Applications
• Secular evolution of compact binaries near massive black holes: gravitational wave sources and other exotica
• On the Eccentricity Distribution of Coalescing Black Hole Binaries Driven by the Kozai Mechanism in Globular Clusters
• The Kozai Mechanism and the Evolution of Binary Supermassive Black Holes
• Binary black hole mergers from field triples: properties, rates and the impact of stellar evolution
• Accelerating Compact Object Mergers in Triple Systems with the Kozai Resonance: A Mechanism for "Prompt" Type Ia Supernovae, Gamma-Ray Bursts, and Other Exotica
• Lidov-Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems
• Four-Body Effects in Globular Cluster Black Hole Coalescence
• Black hole triple dynamics: breakdown of the orbit average approximation and implications for gravitational wave detections
• Rapid Eccentricity Oscillations and the Mergers of Compact Objects in Hierarchical Triples
• On the Relation Between Hot Jupiters & the Roche Limit
• Stellar-mass black holes in young massive and open stellar clusters and their role in gravitational-wave generation II
• Quasi-secular evolution of mildly hierarchical triple systems: analytics and applications for GW-sources and hot Jupiters
• Enhanced Black-Hole Mergers in Binary-Binary Interactions
• An Analytical Portrait of Binary Mergers in Hierarchical Triple Systems
• Spin-Orbit Misalignment of Merging Black-Hole Binaries with Tertiary Companions
• Birth, life, and death of black hole binaries around supermassive black holes: dynamical evolution of gravitational wave sources
• The Effect of Distant Encounters on Black Hole Binaries in Globular Clusters: Systematic Increase of In-cluster Mergers in the LISA band
• Dynamical constraints on the origin of hot and warm Jupiters with close friends
• Compact-Object Mergers in the Galactic Center: Evolution in Triaxial Clusters
• Secular dynamics of binaries in stellar clusters II: dynamical evolution
• Compact object binary mergers driven by cluster tides: a new channel for LIGO/Virgo gravitational wave events
• Binary black holes mergers from hierarchical triples in open clusters
• Secular dynamics of binaries in stellar clusters -- III. Doubly-averaged dynamics in the presence of general relativistic precession