Where to find Electromagnetic Wave Counterparts of stellar-mass binary black hole mergers?

TL;DR

This paper proposes that binary black hole mergers in gaseous disks around supermassive black holes can produce detectable electromagnetic counterparts, specifically transient radio flares similar to fast radio bursts, enhancing multi-messenger astronomy.

Contribution

It introduces a novel scenario where BBH mergers in gaseous environments produce observable EM signals, expanding the potential for multi-messenger detections.

Findings

GW-derived mass and spin can identify such mergers

Predicted radio flares resemble fast radio bursts

Potential to observe mergers at greater distances

Abstract

Multi-messenger astronomy combining Gravitational Wave (GW) and Electromagnetic Wave (EM) observation brings huge impact on physics, astrophysics and cosmology. However, the majority of sources to be detected with currently running ground-based GW observatories are binary black hole (BBH) mergers, which are expected disappointedly to have no EM counterparts. In this letter, we propose that if the BBH merger happens in a gaseous disk around a supermassive black hole, the merger can be accompanied by a transient radio flare alike a fast radio burst (FRB). We argue that the total mass and the effective spin derived from GW detection can be used to distinguish such a source from other channels of BBH mergers. If the prediction is confirmed with future observation, multi-messenger astronomy can be brought to a distance which is one order of magnitude farther than present. The mystery of the origin of FRBs can also be revealed partially.