# Binary Mergers near a Supermassive Black Hole: Relativistic Effects in Triples

## TL;DR

This paper investigates how relativistic effects near a spinning supermassive black hole influence the orbital and spin dynamics of merging black hole binaries in triple systems, potentially affecting merger rates and spin orientations.

## Contribution

It introduces the concept of a 'GR-enhanced' merger channel where relativistic precessions expand the conditions for black hole binary mergers in hierarchical triples.

## Key findings

- Relativistic effects increase the inclination window for mergers.
- They produce a wide range of spin orientations at LIGO detection.
- The 'GR-enhanced' channel may significantly impact black hole merger rates.

## Abstract

We study the general relativitic (GR) effects induced by a spinning supermassive black hole on the orbital and spin evolution of a merging black hole binary (BHB) in a hierarchical triple system. A sufficiently inclined outer orbit can excite Lidov-Kozai eccentricity oscillations in the BHB and induce its merger. These GR effects generate extra precessions on the BHB orbits and spins, significantly increasing the inclination window for mergers and producing a wide range of spin orientations when the BHB enters LIGO band. This "GR-enhanced" channel may play an important role in BHB mergers.