DR. KUNAL MOOLEY

According to GR, the mergers of binary black hole and neutron star systems should give rise to gravitational waves (GWs). Ground-based interferometers like aLIGO expect detections of GWs from BH-NS and NS-NS mergers within this decade. Maximizing the science returns from aLIGO detections will require the identification and detailed study of their electromagnetic (EM) counterparts. While distinct signatures of binary compact star mergers are expected in the X-rays, optical and infrared, their timescales of evolution are extremely short (hours~day). However, with the ability to capture dust-obscured phenomena and the interactions between fast outflows and the surrounding media, radio afterglows offer unique discovery opportunities and strong diagnostics for the merger events. At the same time, poor localization of aLIGO sources, the slow evolution (months~years) of radio afterglows present challenges to the search for radio counterparts of GW sources. In this talk, the speaker will introduce the ongoing efforts for finding EM counterparts of GW sources, especially at radio wavelengths; give a description of the expected EM signatures; and argue that radio observations are just as powerful as the optical, if not more, for detecting the counterparts of GW sources. He will end by briefly describing also the prospects of finding the radio counterparts of GW sources, such as binary SMBH mergers, relevant for space-based interferometers and pulsar timing arrays.