Plotting the cross-correlated DARM noise (band 5) and LEVA temperature on the same plot doesn't show any obvious relationship. The .fig is included in case someone has a good idea of how to use this data.
This analysis has been inspired by the recent investigations on the L1 noise , that shows some correlation of DARM variations vs LVEA temperature. By superimposing the current best L1 curve and the best H1 curve from O1 (see plot), one can see that the noise in the L1 bucket seems to have more "scattering looking" peaks (which can be modulated by temperature-induced alignment variations), while the H1 noise less so. The noise at high frequency is notably lower in L1, mostly due to the higher cavity pole frequency.
I have extended Matt's previous analysis to the entire O1. In addition, I added another interesting channel, the vertical sensor of the top stage of ITMY. Here is the result.
I went through trend of some interesting channels where I was looking for signals showing similar variation to the band limited rms of the cross spectra. I came across ITMs' top stage vertical monitors and found them showing two relatively big bumps (actually dips in the raw signals) which seemingly match the ones in the band limited rms on Dec 2nd and Dec 29th. However, even through they look like showing a good agreement in the last half of the O1 period, the first half does not show an obvious correlation. Does this mean that the modulation mechanism of the noise level changed in the middle of the run and somehow noise level became sensitive to vertical displacement of ITMs or in-chamber temperature ?
For completeness, I have looked at other vertical monitors. Here is the result. They all show qualitatively the same behavior more or less. The fig file can be found on a server.
