26-30 July 2021
Europe/Berlin timezone

Anchoring supermassive black hole binaries to active galactic nuclei with the gravitational-wave background

Not scheduled


Poster Astroparticle and Gravitational Waves T01: Astroparticle and Gravitational Waves


J. Andrew Casey-Clyde (Department of Physics, Unniversity of Connecticut)


The nanohertz gravitational wave background (GWB) is believed to be dominated by emission from supermassive black hole binaries (SMBHBs). This population's properties have commonly been investigated using major galaxy mergers as a proxy for SMBHB formation. However, the observation of several dual active galactic nuclei (AGN) strongly suggests a link between AGN and SMBHBs, given that these dual AGN systems will eventually form a bound binary pair. Here we present a complementary model of the SMBHB population using AGN as a proxy for SMBHB systems instead of galaxy mergers. We compare the GWB generated by this AGN-proxy model and its major merger counterparts to the common-spectrum process in the NANOGrav 12.5-yr dataset. Finding the GWB generated by these models to be generally lower, we estimate how many more SMBHB sources are needed to generate a background like the NANOGrav 12.5-yr signal.

Email andrew.casey-clyde@uconn.edu
Collaboration / Activity NANOGrav
First author J. Andrew Casey-Clyde

Primary authors

J. Andrew Casey-Clyde (Department of Physics, Unniversity of Connecticut) Prof. Chiara Mingarelli (Department of Physics, University of Connecticut; Center for Computational Astrophysics, Flatiron Institute) Prof. Jenny Greene (Department of Astrophysical Sciences, Princeton University) Dr Kris Pardo (Jet Propulsion Laboratory, California Institute of Technology) Morgan Nañez (Department of Astronomy, University of California Berkeley) Dr Andy Goulding (Department of Astrophysical Sciences, Princeton University)

Presentation Materials