MOCCA-SURVEY Database. I. Eccentric Black Hole Mergers during Binary-Single Interactions in Globular Clusters
Abstract
We estimate the population of eccentric gravitational wave (GW) binary black hole (BBH) mergers forming during binary-single interactions in globular clusters (GCs), using ∼800 GC models that were evolved using the MOCCA code for star cluster simulations as part of the MOCCA-Survey Database I project. By re-simulating BH binary-single interactions extracted from this set of GC models using an N-body code that includes GW emission at the 2.5 post-Newtonian level, we find that ∼10% of all the BBHs assembled in our GC models that merge at present time form during chaotic binary-single interactions, and that about half of this sample have an eccentricity >0.1 at 10 Hz. We explicitly show that this derived rate of eccentric mergers is ∼100 times higher than one would find with a purely Newtonian N-body code. Furthermore, we demonstrate that the eccentric fraction can be accurately estimated using a simple analytical formalism when the interacting BHs are of similar mass, a result that serves as the first successful analytical description of eccentric GW mergers forming during three-body interactions in realistic GCs.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2018
- DOI:
- 10.3847/1538-4357/aaab52
- arXiv:
- arXiv:1712.06186
- Bibcode:
- 2018ApJ...855..124S
- Keywords:
-
- galaxies: star clusters: general;
- gravitation;
- gravitational waves;
- stars: black holes;
- stars: kinematics and dynamics;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 5 pages, 1 figure, revised manuscript has been accepted for publication in ApJ