Below is the summary of the DQ shift for the week of 2023-07-03 to 2023-07-09
- The detector had very good uptime this week (observing 77%), and the range was consistently around 140 Mpc with a few Mpc fluctuations. During the last couple of days, it was on the lower side.
- The reasons for most of the lock losses reported to be unknown.
- Almost all the locks begin with high violin modes, with rung-up violin modes even at 3 - 4 kHz. Between a lockless and relock, something seems to ring them up (alog 71063).
- The ~52 Hz line-like feature has gotten strong and changes its amplitude over hours time scale. We also see ~26.50 Hz, ~39.25 Hz, and 65.75 Hz features but not all simultaneously. The 52 Hz feature is dominant among these and shows a lot of variability. Sometimes the 52 Hz also looks like a two-line feature at that frequency. In the X-end accelerometers, we also see similar features, but it is unclear whether they are related to each other (we don't see strong coherence, not at least at 0.125 Hz resolution).
- The noise in the 10 - 60 Hz also varies a lot. It is also suggested that some of these features could come from calibration lines (non-linear/bilinear effects) (alog 71149).
- There is excess noise around the 120 Hz line, but it is mainly on the higher frequency side of it.
- Most strong omicron glitches tend to occur at specific frequencies like ~32 Hz, ~40 Hz, ~50 Hz, ~74 Hz, ~120 Hz, ~180 Hz, ~280 Hz, and ~400 Hz.
- We also see a wandering line at 4620 Hz (a few tens of Hz wander).
- In the Fscan, we see combs of 1.6611 Hz, 29.969 Hz, and 4.9842 Hz. They are present during the whole week.
- Sometimes we see excess noise in the PCALX RX and TX channels, but it does not seem to affect DARM (low amplitude ?).
- On July 5 and 6, we see step changes in the corner station's 10-30 Hz seismic BLRMS. It also appears in other ground motions (ACC) channels at specific frequencies (some pumps turning off ?).
- In Hveto, we see some of the ASC channels and EX_VMON_ETMX_ESDPOWER as the first few round winners. They tend to remove some of the large glitches we see.
- We see a relatively large number of glitches in the pyCBC short-duration triggers (with new SNR > 9).
The full DQ shift report with day by day details is available at https://wiki.ligo.org/DetChar/DataQuality/DQShiftLHO20230703