# On the Assembly Rate of Highly Eccentric Binary Black Hole Mergers

## TL;DR

This paper calculates the fraction of highly eccentric binary black hole mergers from binary-single interactions, suggesting such events are common in globular clusters and could be key to understanding their astrophysical origins.

## Contribution

It introduces a method using N-body simulations with post-Newtonian corrections to estimate the rate of high-eccentricity BBH mergers from dynamical interactions.

## Key findings

- Over 1% of BBH mergers from this channel have e>0.1 in LIGO band
- Binary-single interactions likely dominate high-eccentricity BBH mergers in globular clusters
- High eccentricity mergers can help identify their astrophysical formation channels

## Abstract

In this {\it Letter} we calculate the fraction of highly eccentric binary black hole (BBH) mergers resulting from binary-single interactions. Using an $N$-body code that includes post-Newtonian correction terms, we show that $\gtrsim 1\%$ of all BBH mergers resulting from this channel will have an eccentricity $e>0.1$ when coming into the LIGO frequency band. As the majority of BBH mergers forming in globular clusters are assembled through three-body encounters, we suggest that such interactions are likely to dominate the population of high eccentricity BBH mergers detectable by LIGO. The relative frequency of highly eccentric events could eventually help to constrain the astrophysical origin of BBH mergers.