GRG Editor's Choice: Busting up binaries: encounters between compact binaries and a supermassive black hole

© SpringerAddison, E., Gracia-Linares, M., Laguna, P., Larson, S.L., Busting up binaries: encounters between compact binaries and a supermassive black hole, Gen Relativ Gravit (2019) 51: 38.​​​​​​​

Editor's Choice (Research Article)

First Online: 05 March 2019


Close encounters between compact object binaries and a supermassive black hole are plausible at galactic centers. We present results from a numerical study of close to 13 million such encounters. Consistent with previous studies, we found that disrupted binaries produce bound extreme-mass-ratio binaries with eccentricities of ∼0.97 which circularize dramatically by the time they enter the classical LISA sensitivity band. We also investigated the regions of parameter space for binary survival and estimated the distribution of orbital parameters post-encounter. Our results showed that the semi-major axis of the population of surviving binaries is not significantly affected by the encounter. On the other hand, the eccentricity does; it increases in most cases. As a consequence, the encounter with the super-massive black hole accelerates the merger of the surviving binary, increasing the predicted merger rates by up to 1%.

The authors: 

GERG EC image © by authors​​​​​​​Eric Addison graduated from Utah State University in 2014 with a thesis on "Gravitational Wave Astrophysics with Compact Binary Systems". After doing research and software development for Chevron, he is now a software engineer at Google. 

Miguel Gracia-Linares is a Postdoctoral Researcher in the Center for Relativistic Astrophysics at Georgia Institute of Technology.

Pablo Laguna is Professor and Chair of the School of Physics and member of the Center for Relativistic Astrophysics at Georgia Institute of Technology. His research is in computational astrophysics and numerical relativity.

Shane L. Larson is a Research Associate Professor at Northwestern University and the Associate Director of the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

GRG Editor's Choice:

In each volume of GRG, a few papers are marked as “Editor’s Choice”. The primary criteria is original, high quality research that is of wide interest within the community.