Recording gravity waves over the noise floor

[musichascolors]

I'm curious as to how the gravity waves were recorded given how small the amplitude of the wave was/is. Was it not below the thermal noise floor? Were noise removal techniques used, etc?

Also, what kind of sampling rate/bit depth was used?

Thanks

 

[mfb]

You probably mean gravitational waves. Gravity waves are water waves, for example.
As you can see in the publications, the noise was smaller than the observed signal, and a lot of effort was put into noise reduction.
All the other details are in the publications as well.