Flares from coalescing black holes in the centimeter-wavelength transient sky

TL;DR

This paper explores how the next-generation radio array can detect and localize electromagnetic signals from merging supermassive black holes, enabling cosmological measurements and insights into black hole evolution.

Contribution

It demonstrates the potential of ngVLA to identify and study prompt radio counterparts to SMBH mergers detected by LISA, advancing multi-messenger astronomy.

Findings

Potential for ngVLA to localize SMBH coalescence counterparts.

Ability to measure redshifts and build a Hubble diagram.

Insights into SMBH environments and formation mechanisms.

Abstract

Radio observations have resulted in some of the most fundamental and exciting discoveries in time-domain astronomy. Here I demonstrate the potential for the Next Generation Very Large Array (ngVLA) to localize prompt centimeter-wavelength counterparts to the coalescing binary supermassive black holes (SMBHs) to be detected by the LISA mission. The resulting redshift measurements of the hosts of LISA-detected coalescences will populate a Hubble diagram up to the epoch of the earliest galaxies. Analysis of the host environments and the electromagnetic coalescence signatures will provide crucial insight into the interactions between binary SMBHs and their environments, and the mechanisms of SMBH formation and growth.