I'm always a step behing the on-site commissioners (good job!), but here is the list of coherence for the 2+ hours lock:

https://ldas-jobs.ligo.caltech.edu/~gabriele.vajente/bruco_1107760396/

Here are my main comments on it:

• In the low frequency range (below 20 Hz) there is coherence with some suspension signals from HAM1, HAM2, ITMY, see the first three attached plot for some examples. In particular coherence is high with HAM1/2 at 15 Hz and ITMY at 30 Hz. I'm not very familiar with those systems, so I probably didn't choose very meaningful channels, but if you look into the full table you'll see many of them.
• It's not high, but nevertheless significant: there's coherence between 10 and 100 Hz with PEM-EY_MAG_VEA_FLOOR_*
• Between 40 and 1000 Hz there is broadband, even if not large, coherence with POP_LF, probably due to intensity noise. However, this is the largest coherence in most of this band
• At 75 Hz there is coherence with the magnetometers at the Y end: I guess it's the well known ring heater line
• There is a "bump" of coherence with IMC angular signals between 287 and 300 Hz. This might be one of the beam jitter resonances. There are similar bumps at about 550 Hz and 820 Hz