ITF found locked and stable at around 50 Mpc. At 15:25 UTC there were a first Fast unlock, I was able to reach LOW_NOISE_3 again at 16:05 UTC but from 16:50 UTC to 17:35 UTC there was a Fast Unlock Crisis. I waited in DOWN state until the end of the instability, ITF locked again at 17:58 UTC.
The last lock seems mostly stable at 50 Mpc, but from 20:00 UTC the Horizon went down to 37 Mpc. F. Sorrentino briefly verified the phase of the Squeezing Photodiode ( switched to Commissioning Mode from 20:12 UTC to 20:23 UTC ) but that wasn't the cause of the issue. The Horizon returned to its standard value at 20:30 UTC ( see attached plot ).
ITF left Locked in AUTORELOCK_FAILSAFE.
VPM
After a series of lock attempts DET_MAIN resulted stuck at 17:10 UTC. I manually restarted it from VPM and then it was possible to lock again.
TCS
From 15:15 UTC to 15:26 UTC I. Nardecchia went to Laser Lab Atrium to switch off the HWS Sled.
Guard Tour (UTC )
14:33 - 15:15;
16:29 - 17:05;
18:31 - 19:00;
21:14 - 21:48.