I have read that on applying FFT on gravitational wave strain we can bring Amplitude time domain to Amplitude-frequency domain. But when I apply this conversion on the data I had I get this curve
I'm looking at gravitational wave strain data provided by LIGO. I am trying to estimate the mass of the black holes using the waveforms. The equation is present in an amplitude frequency domain. So I'm trying to convert it into that domain from Amplitude time.
How were the solar masses and distance of the GW150914 merger event calculated from the signal?
I am referring to this equation
Is this the expected figure or should I have used something other that FFT, if so what would that be?