Figure 1. There is steady high rate of glitches in the mid-frequency band. I do not remember seeing such an issue in the past few years. It is possible that will resolve itself as the adjustment of the interferometer thermal compensation and controls are in progress, but it is not likely. Starting investigating what are the properties of these glitches should start in parallel of the on-going interferometer tuning.
FWIW, online Bruco wasn't able to run overnight as it didn't find any long enough segment w/o strong glitch.
Daily UPV finds some SDB1 witness channels but they only account for a few percents of those glitches.
I've hacked a Virgo DQR script to zoom onto those glitches over a few minutes -- see plot in attachment
- Top: the Omicron triggers (before time clustering)
- Middle: the standard Omicron clusters (after time clustering; what we usually call Omicron "triggers")
- Bottom: an attempt to make 2D (time-frequency) clusters
=> Most of the strong glitches (dark brown) are short in time and very wide in frequency.
I tried to investigate the correlation between these glitches and the auxiliary channels. First, I identified a BRMS channel from Hrec that could serve as a glitch witness: V1:DQ_BRMSMonHrec_BRMS_HREC_HOFT_FREQ_BAND_85_95_Hrec_hoft_16384Hz seemed like a reasonable choice. I then computed correlations with all _mean and _rms trend channels, as described in a previous entry (#66922).
Fairly high correlations were found with the following channels V1:Sc_WI_FF50HZ_*_rms, and V1:Sc_BS_CMRF_rms V1:SDB2_POWERSUPPLY_DBOX_LEFT_DOWN_p12V_rms.
One possibility is that the observed correlations arise from these channels "reacting" to the loud glitches in the strain channel, rather than being causally related to their origin. Therefore, this study does not appear to provide new insights into the origin of these glitches.
As with the range correlation study (#66922), more information may become available once we have access to longer stretches of undisturbed data in DQ Studies operational mode.
