Three-body capture, ejection, and the demographics of bound objects in binary systems

Abstract

We study the capture of light objects of arbitrary velocity by binary systems. Extending results for the capture of comets in the solar system, we develop a simple geometric characterization of the capture cross section, leading directly to the distribution of orbital parameters of captured objects. We use the same framework to study the lifetimes of these bound orbits prior to ejection, and find that a simplified version of the Öpik--Arnold approach readily yields a closed-form estimate for the ejection rate that agrees well with numerical experiments. Without any detailed-balance assumptions, our results make manifest the characteristics of close encounters leading to capture and ejection. As an application of our results, we demonstrate the estimation of the equilibrium population of captured dark matter particles in a binary system.

arXiv comment12 pages, 6 figures. Matched published version

References in corpus (28)

• REBOUND: An open-source multi-purpose N-body code for collisional dynamics
• Primordial Black Holes as Dark Matter
• The NASA Exoplanet Archive: Data and Tools for Exoplanet Research
• The international pulsar timing array project: using pulsars as a gravitational wave detector
• Defining and cataloging exoplanets: The exoplanet.eu database
• One or more bound planets per Milky Way star from microlensing observations
• Binary neutron-star mergers: a review of Einstein's richest laboratory
• Testing General Relativity with Pulsar Timing
• Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25
• The Exoplanet Orbit Database
• Gravitational waves from coalescing binaries: detection strategies and Monte Carlo estimation of parameters
• A New Probe of Dark Matter and High-Energy Universe Using Microlensing
• Hybrid Symplectic Integrators for Planetary Dynamics
• Pulsars as Tools for Fundamental Physics and Astrophysics
• On the origin of planets at very wide orbits from the re-capture of free floating planets
• Primordial Black Holes as a Probe of Cosmology and High Energy Physics
• Pulsar Timing Probes of Primordial Black Holes and Subhalos
• WIMP diffusion in the solar system including solar depletion and its effect on Earth capture rates
• Free-Floating Planets: Not So Surprising
• Free floating planets in stellar clusters?
• Observability of Dark Matter Substructure with Pulsar Timing Correlations
• Gravitational wave research using pulsar timing arrays
• Close encounters involving free-floating planets in star clusters
• Dark matter in the solar system III: The distribution function of WIMPs at the Earth from gravitational capture
• The Demographics of Rocky Free-Floating Planets and their Detectability by WFIRST
• Implications of Captured Interstellar Objects for Panspermia and Extraterrestrial Life
• Planet seeding through gas-assisted capture of interstellar objects
• Capture of free-floating planets by stellar systems

Cited by in corpus (9)

• Transfer of Rocks between Planetary Systems: Panspermia Revisited
• A halo of trapped interstellar matter surrounding the solar system
• Dark Exoplanets
• Capture of primordial black holes in extrasolar systems
• Dancing with invisible partners: Three-body exchanges with primordial black holes
• Gravitational wave signals from primordial black holes orbiting solar-type stars
• Hawking Radiation Signatures from Primordial Black Holes Transiting the Inner Solar System: Prospects for Detection
• Gravitational Ionization by Schwarzschild Primordial Black Holes
• Fast and Fewrious: Stochastic binary perturbations from fast compact objects