TITLE: 08/05 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 12mph Gusts, 6mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.09 μm/s
QUICK SUMMARY: H1 has been locked for 17 hours, but looks like there were three brief drops from observing between 11:33 and 11:40 UTC (I'm assuming SQZ-related, but will look into it). Magnetic injections are running and in-lock charge measurements will happen right after before maintenance begins at 15:00 UTC.
Lockloss happened during in-lock charge measurements, specifically during the 12Hz injection to ETMX. The lockloss tool tags IMC for this one, and it certainly looks like the IMC lost lock first, but I can't say for sure why.
The three drops from Observing that Ryan points out were actually from the CO2 lasers loosing lock, first CO2Y and then CO2X lost lock twice, all between 11:33 and 11:40UTC ~4:30amPT. Both PZTs and laser temperatures started changing ~5minutes before CO2Y last lock. Unsure what would make this happen, LVEA temperature and chiller flowrates as recorded in LVEA were stable, see attached.
Unsure of the reason for this, especially as they both changed at the same time but are for the most part independent systems (apart from shared RF source). We should watch to see if this happens again.
My initial thought was RF, but the two channels we have to monitor that both looked okay around that time. About 4 minutes before the PZTs start to move away there is maybe a slight change in the behavior of the H1:ISC-RF_C_AMP10M_OUTPUTMON channel (attachment 1), but I found a few other times it has similar output and the laser has been okay, plus 4 minutes seems like too long for a reaction like this. The pzts do show some type of glitching behavior 1-2 minutes before they start to drive away that I haven't found at other times (attachment 2). This glitch timing is identical in both laser's pzts.
I trended almost every CO2 channel that seemed worthwhile, I looked at magnetometers, LVEA microphones, seismometers, mainsmon, and I didn't find anything suspicious. The few people on site weren't in the OSB. Not sure what else to look for at this point. I'm wondering if maybe this is some type of power supply or grounding issue, but I'd expect to see it other places as well then. Perhaps places I just haven't found yet.