http://arxiv.org/abs/1907.03746
Accretion disks around supermassive black holes are promising sites for stellar mass black hole (BH) mergers due to mass segregation and merger acceleration by disk gas torques. At BH merger, a few percent of the mass is lost, generating gravitational waves detectable with Advanced LIGO and Advanced Virgo. The mass loss causes the merging system’s sphere of influence, known as the Hill sphere (radius $R_H$), to contract at light speed, and gas within the Hill sphere will self-collide. Observational signatures will depend on how $R_H$ compares to the accretion disk height, $H$. If $R_{H}\geq H$, a UV flare emerges post-merger on timescale $R_{H}/c$. A thermalized disk hot spot alters the AGN optical/UV photometry and asymmetric broad emission line profiles can develop. If $R_{H}<H$, detectability depends strongly on the disk optical depth. Large optical sky surveys can be used now, during O3, to search for BH mergers in AGN disks. LIGO/Virgo triggers should include rough mass estimates to optimize follow-up.
B. McKernan, K. Ford, I. Bartos, et. al.
Tue, 9 Jul 19
41/81
Comments: 5pages, 2 figures, ApJL (submitted)
You must be logged in to post a comment.