TITLE: 07/24 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
SHIFT SUMMARY:
23:17 Detector locked for 7:51 and in Observing
00:41 Moved itself out of Observing and into Commissioning, and then immediately lost lock (71635). H1_MANAGER did good with relocking
1:36 Got into OMC_WHITENING
2:25 Moved into NOMINAL_LOW_NOISE
2:26 Got into Observing
3:10 On SEISMON_ALERT bc of incoming earthquake from Tonga
3:52 Back to CALM
4:09:01 Pushed out of Observe and into Commissioning by SDF_DIFF syscssqz but diffs immediately disappeared
4:09:10 I put us back into Observing
7:00 In Observing and Locked for 4:36
Relocking after the lockloss went smoothly and quickly.
ISC_LOCK went through CHECK_VIOLINGS_BEFORE_POWERUP so quickly that Verbals didn't even register it.
Dust in the PSL got up to 440pcf >300nm around 2:40
LOG:
No log
At this time some of the SQZ GRDs changed. I looked into these syscdsqz sdf diffs, by looking though sdf all channels table for sdf diffs recently changed and trending them. It was H1:SQZ-FIBR_SERVO_COMGAIN and H1:SQZ-FIBR_SERVO_FASTGAIN that changed from 20 to 17 and 15 during this 04:09UTC time, see attached. Unsure what this means. Tagging SQZ.
Naoki, Camilla
We looked at the different TTFSS channels as Daniel and Vicky suggested that a PD could be reaching it's threshold and making the TTFSS think it's unlocked or similar but we seen nothing suspicious, see attached. H1:SQZ-FIBR_EOMRMS channels show a change but we this could be because of the gain change rather than causing the gain change. It was also seen in 71653.