Figure 1 shows the improvement on the interferometer signal. The clearest improvement is visible on B2 PD2 8MHz, where after taking into account the PD sensing noise the lower limit on the 500Hz noise improvement is a factor 7, consistent with an expected improved from the electronics noise measurement of a factor 9. So in principle we could turn back on the 8MHz sideband, use that signal again for PR longitudinal control. Or at least increase it to improve the SNR of alignment signals based on the 8MHz modulation which are still in loop.
On B4 DC there is also a clear improvement, but much smaller as that noise was not very dominant. There is also a modest (~20%) improvement on the two out-of-loop measurement of laser frequency noise (quadrature of SSFS signal, and B2 6MHz).
