# What happens to the accretion disk when two black holes merge

I'm aware that accretion disks around black holes are formed from the swirling mass of matter that is slowly being stripped of its atoms, but what happens to it when two black holes merge? I was thinking maybe it gets eject or sucked in completely. Not sure why though.

• For a typical black hole merger the radiated power is $\sim10^{49}$ W. This translates into a pressure of about $10^{32}$ Pa near the event horizon. This is a tremendous pressure, but it would be very inefficiently coupled to the accretion disk, since matter is essentially transparent to gravitational waves. So my guess is that the accretion disk almost doesn't notice that anything is happening. It just keeps infalling. – Ben Crowell Nov 19 '19 at 2:29
• Interesting thought, I think it's best I try referring to literature or try simulating it. – DJKG Nov 19 '19 at 18:11