Lockloss - no immediate environmental or other cause. Will continue investigating as we relock.

TITLE: 02/16 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: One lockloss this shift at the end of calibration sweeps and H1 has been trying to relock since. [OpsInfo] I've put new damping settings for ETMY mode 20 into the Guardian and loaded; these have been working well the past couple of days.

• 19:30 - Dropped observing for scheduled calibration sweeps - alog82827
• 20:01 - Lockloss at end of sweeps
  • Went immediately into initial alignment, ran automatically
  • Been a long relock due to two locklosses at TRANSITION_FROM_ETMX and lots of random dropouts during ALS, FIND_IR, and DRMI with no clear causes. Microseism has been higher this afternoon, but generally alignment has been good and signals have looked stable

TITLE: 02/16 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 3mph Gusts, 1mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.60 μm/s
QUICK SUMMARY:

IFO is in LOCKING

Having a lot of issues, starting with a LL due to a failed Cal Sweep. Since then, DAY Ops (Ryan S) has experienced locking issues at ALS, IR, DRMI and TRANSITION_ETMX. Interestingly, despite high microseism, ALS locking doesn't look noisy and IFO seems to lose lock without evidence of high ground motion.

Will continue investigating, troubleshooting and locking.

While attempting to lock H1 this afternoon, occasionally I would notice the ALS-X transmission get a bit noisy, then it would drop out entirely and there would be a lockloss. On a couple of the more recent instances of this, there was also an MC2 saturation callout right before the lockloss, leading me to believe the IMC was having trouble staying locked. The RefCav alignment has been dropping over the past several days (likely due to the change in weather) and has needed an adjustment, so, thinking that might help the IMC, I paused between lock attempts to touch up the RefCav alignment using the picomotor mirrors in the FSS path. I was only able to improve the signal on the TPD from about 630mV to 740mV in the few minutes I spent, but I was about at the limit of improvement I think I could get. I'm not sure if this helped at all as H1 still has yet to relock, but I figure this is still an improvement.

Following the wiki instructions, I ran broadband and Simulines calibration sweeps this morning. This was with the updated Simulines sweep from Vlad with the last frequency point cut out, however H1 again lost lock towards the end of the Simulines injections (link to lockloss tool). See previous investigations into these locklosses in alog82704.

The following injections were the ones still running at the time of the lockloss at 20:01:53 UTC:

Broadband sweep ran from 19:30:50 to 19:36:06 UTC, Simulines sweep ran from 19:36:53 to 20:01:53 UTC (ended at lockloss). The 7.68Hz DARM injection is clearly seen on the lockloss trends.

Sat Feb 15 10:07:24 2025 INFO: Fill completed in 7min 20secs

TCmins [-48C, -46C] OAT (-3C, 27F) DeltaTempTime 10:07:23

TITLE: 02/15 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 1mph Gusts, 0mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.47 μm/s
QUICK SUMMARY: H1 has been locked for 8.5 hours with inspiral range increasing over this stretch due to decreasing noise at high frequency. (Perhaps SQZ phase? Trend attached)

• ETMY mode 20 is around 2.68 with the gain having been off this lock, but I've engaged FM1+FM3+FM10 G=-1.0 to see if that keeps working
• Wind is low, secondary microseism mostly steady right below 90th percentile

TITLE: 02/15 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Locking
INCOMING OPERATOR: Corey
SHIFT SUMMARY:

IFO is in NLN and OBSERVING as of 04:16 UTC.

EDIT: IFO is LOCKING at SDF_REVERT after a 05:59 UTC Lockloss

Overall calm shift with one lockloss due to an Earthquake (alog 82821).

Other:

• We also survived another earthquake (4.9 from W Texas).
• Range is quite low due to bad high frequency squeezing, which I was told to expect. This will probably remain the case until more table work is done next week.
• I tried (from Sheila and Ryan S's recommendation) a small test to see if going into GREEN_ARMS_MANUAL, locking the arms manually, then going through in INITIAL_ALIGNMENT_OFFLOADED would bypass our ALS locking failures. Interestingly, this worked, allowing us to lock with normal locking without running into ALS problems - the investigation continues.
• Ryan's new FM 1,3,10 -1G EY Violin Mode 20 seems to have worked, reaching a pre-LL minimum of 0.18 before nouncing about that. As such after the reacquisition, I re-set those as the EY20 settings.

LOG:

None

Lockloss due to 5.7 EQ in Mongolia. Initially I thought we rode it out since the EQ happened since verbal sounded it 30 minutes before losing lock. Though looking at the later arriving R waves, we seem to have lost lock 3 minutes after they were detected by ISI Sensors, microseism FOM and Picket Fence. Right after the LL, EQ mode activated. High secondary microseism likely contributes to higher EQ susceptibility too.

Shall begin to re-lock once it passes.

Robert, Tyler, Richard, Eric, TJ

Several years ago we were unable to lock because the suspensions were getting hot and lengthening when it was very cold out. The problem was that our temperature control sensors were mounted on the walls, and were influenced by the temperature of the walls. As a result, the HVAC overheated the LVEA to keep the wall sensors at the same temperature when it was very cold out, or over-cooled the LVEA when the sun shown on the walls (33320). We moved some of the sensors to cable trays by the vacuum enclosure to combat this problem, but, since the sensors on the cable trays dont provide full coverage, we still use many of the wall sensors. Yesterday we took more of the wall sensors out of the control average because we are having some problems in this cold snap with the suspensions lengthening.

In addition, TJ altered the LVEA temperature figure of merit to focus on the sensors on the cable trays so that we would be alerted to temperature increases at the chambers, where previously we were mainly monitoring the temperature at the walls.

The figure shows which sensors are now being used (checked boxes). It also shows the new FOM - the first 4 channels are on cable trays near the IFO.

TITLE: 02/15 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: One lockloss this shift with a relatively straightforward relock. SQZ isn't performing perfectly, so range has been inconsistent and possibly will be also through the weekend.

• 15:30 - H1 relocking
• 16:47 - Observing
• 17:34 - Dropped observing for SQZ FC to relock
• 17:37 - Observing
• 21:15 - Lockloss - alog82809
  • 21:35 - Starting initial alignment
  • 22:49 - Reached NLN, running A2L
• 23:11 - Observing

LOG:

TITLE: 02/15 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 24mph Gusts, 15mph 3min avg
    Primary useism: 0.05 μm/s
    Secondary useism: 0.37 μm/s
QUICK SUMMARY:

IFO is in NLN and OBSERVING as of 22:49 UTC

Range is low due to poor high freq squeezing, which Sheila and Ryan were troubleshooting when I walked in - will probably be bad over the weekend since this long standing issue is still somewhat a mystery and likely needs table work.

Additionally, love is both in the air and the walls.

Jennie W, Rick S, Mayank C, Keita K

We went into the optics lab today with the intent for Rick to review the ISS array assembly we unboxed the other day (LHO alog #82731) on which we found some particulate contaminsation and some detached parts.. Rick and Keita are unsure how the support rods (first picture) were bent during transit and they appear to have bent at the top and deformed the cover piece (D1300717) they were attached to as they came unfixed at the other end and so were just resting on the top of the QPD mount plate (D1300719). They appear to have moved around and scored the surface of this platform. Maybe this happened in transit or storage but it seems like it would have had to be a large force and Rick says the storage containers were packed in form during transit.

1st package: Base piece (D1101074-v2 S/N 004) is double-bagged in my office and I have put in a clean and bake order as this spacer is site specific in height and some of our ISS spares will have a spacer set to the L1 beam height instead so we may need to swap it out.

2nd package: Cover piece D1300717 with the spacing posts attached is not bagged properly as we probably do not want to reuse this and so it is in Keita's office.

3rd package: Array and mirror assembly with PDs still attached was wrapped in foil with dry sealed clean room wipes protecting top optic in periscope, then double-bagged. Shown in center left of this image. This will need re-cleaned if we want ot scavenge parts form it.

4th package: All the other parts from assembl y shown in this image ( apart from PD assembly, baseplate, tool pan and top cover) have been packaged up in foil and double bagged in one package. These will also need recleaned if reused.

These last two packages are stored in the cabinet that the spare ISS array units are in, situated in the vacuum bake prep area next to the PCal lab. The shipping cover and base plate for the array are also back in this cupboard.

For reference the assembly drawing can be found here.

The assembly we worked on has the dcc ref S12020967

Robert, Jennie, Keita, Mayank, Rick

People working in the optics lab noticed a sudden infestation of winged termites, unmated queens and kings participting in a nuptial flight. We found the nest from which they had emerged, full of alates and immature termites, in the wall behind the flow benches (see figure), and possibly extending into the fan boxes of the flow benches, which are wooden. We temporarily sealed up the nest entrance (see figure) but we should probably deal with the colony, both because of damage from feeding, and because there will be occasional mating flights from the colony.

Lockloss @ 21:15 UTC - link to lockloss tool

The lockloss tool tags this as WINDY (although wind speeds were only up to around 20mph) and there seems to be an 11Hz oscillation that starts about a second before the lockloss seen by all quads, PRCL, MICH, SRCL, and DARM.