Reports until 14:23, Thursday 27 July 2023
H1 DetChar (DetChar, PEM)
andrew.lundgren@LIGO.ORG - posted 14:23, Thursday 27 July 2023 (71772)
Jitter glitches from control room activity
Marissa, Shania, Tabata, Gaby, Brennan, Andy

While looking into jitter glitches (alog 71739), we found a time with a few similar glitches on July 17th. They happen when fiber was being pulled from the control room to the fire panel (alog 71416).

The glitches have a similar appearance to the previous jitter glitches (plot 1), and are witnessed by the IMC and PSL periscope accelerometer, so they are probably through the same coupling mechanism. Plot 2 shows the Omicron triggers (21:12 to 21:18 UTC). The motion is very visible in the LVEA floor accelerometer near HAM1 (plot 3, compare to plot 4 of DARM), and also on many other PEM channels.

A full Omega scan of one of these glitches is here.
Images attached to this report