We lost lock just as I was beginning  HVAC shutdowns to take advantage of the nearly 160 Mpc range. When we regained lock, the range was only about what it was for my last shutdown (77477), so I will defer.  Here are the times for what I did do:

Lockloss @ 23:57 UTC - link to lockloss tool

Ends lock at 6 hours. No obvious cause, and I don't see the ETMX motion prior to this lockloss as we've seen in the past.

TITLE: 06/29 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: One lock loss with a straight forward relock, and then a delayed calibration measurement. We've been locked for 5.5 hours.
LOG:

• 1655 Lock loss
• 2106-2133 Out of observing for coordinated calibration

TITLE: 06/29 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 6mph Gusts, 4mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY: H1 has been locked for 5 hours.

• Wind and microseism are low
• All other systems nominal

Calibration sweep taken today at 2106UTC in coordination with LLO and Virgo. This was delayed today since we were'nt thermalized at 1130PT.

Simulines start:

PDT: 2024-06-29 14:11:45.566107 PDT
UTC: 2024-06-29 21:11:45.566107 UTC
GPS: 1403730723.566107

End:

PDT: 2024-06-29 14:33:08.154689 PDT
UTC: 2024-06-29 21:33:08.154689 UTC
GPS: 1403732006.154689
 

I ran into the error below when I first started the simulines script, but it seemed to move on. I'm not sure if this frequently pops up and this is the first time I caught it.

Traceback (most recent call last):
 File "/var/opt/conda/base/envs/cds/lib/python3.10/multiprocessing/process.py", line 314, in _
bootstrap
   self.run()
 File "/var/opt/conda/base/envs/cds/lib/python3.10/multiprocessing/process.py", line 108, in r
un
   self._target(*self._args, **self._kwargs)
 File "/ligo/groups/cal/src/simulines/simulines/simuLines.py", line 427, in generateSignalInje
ction
   SignalInjection(tempObj, [frequency, Amp])
 File "/ligo/groups/cal/src/simulines/simulines/simuLines.py", line 484, in SignalInjection
   drive.start(ramptime=rampUp) #this is blocking, and starts on a GPS second.
 File "/var/opt/conda/base/envs/cds/lib/python3.10/site-packages/awg.py", line 122, in start
   self._get_slot()
 File "/var/opt/conda/base/envs/cds/lib/python3.10/site-packages/awg.py", line 106, in _get_sl
ot
   raise AWGError("can't set channel for " + self.chan)
awg.AWGError: can't set channel for H1:SUS-ETMX_L1_CAL_EXC
 

Andrei, Naoki, Sheila

For the upcoming measurement of the FC backscattering, we need to calibrate the length change of the FC. To do this, we calculated the transfer function from the GS_SL FC control signal [Hz] to FC2 displacement [μm]. We followed the steps in Diagram.png to get to result. The plot bode_all_datasets.png contains all the used datasets.

The resulting transfer function is presented here: Tranfer_func.png (where Result curve is the transfer function). The result was exported to frequency/magnitude/phase dataset and can be found in result_data.txt. The remaining .txt files contain all the used datasets for this calculation.

Assuming that the frequency of the FC resonance shift Δf equal to c/2L corresponds to the FC length change ΔL equal to λ/2. (λ = 532 nm, L = 300 m), then Δf/ΔL = c/(L * λ) = 1.88*10¹²  [Hz/m] = 1.88*10⁶  [Hz/μm]. Multiplying Transfer function by this coefficient will get us the open loop unity gain frequency of 39.4 Hz. Open-loop gain plot (after multiplication) can be found in the following figure: openloop_gain.png.

The long ramp time was confusing me while I was trying to adjust the TMS to speed up locking, so I looked into what needed such a long ramp. I thought it was the TMS servo, but it seems to only use the TEST bank. I couldn't find another place in ISC_LOCK or the ALS guardians that specifically referenced this bank, so I changed it to 2sec like for TMSY and then accepted it in SDF safe and observe. We made it through this acquisition at 2sec so maybe we're OK.

Sat Jun 29 10:09:48 2024 INFO: Fill completed in 9min 45secs

Lockloss 1403715367

There was ground motion from an earthquake just after the lock loss, but the lock loss itself seemed to be quite sudden. ETMX sees those usual wiggles that we often see.

Robert had just started running HVAC shutdown tests, but this seems very unlikely to be the cause.

TITLE: 06/29 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 5mph Gusts, 4mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY: Locked for 8 hours, calm environment after the earthquake settled down.

TITLE: 06/29 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY: Two locklosses this shift and recovery was straightforward in both cases. Earthquakes at the end of the shift shook things up, but ultimately H1 rode through. H1 has now been locked and observing for almost 2 hours.

• 03:06 - Lockloss - alog78735
• 04:14 - Observing; mostly automated relock
• 05:35 - Lockloss - alog78737
• 06:29 - Observing; automated relock
• 07:41 - Two incoming EQs from Peru (6.1 and 5.3; likely aftershocks from 7.0 yesterday)
  • SEI_ENV correctly transitioned to EQ mode early from Picket Fence trigger
  • 07:50 - SRM saturation
  • Both R-waves have passed

LOG: No log for this shift.

Lockloss @ 05:35 UTC - link to lockloss tool

End of short lock, no obvious cause. I don't see the same ETMX motion as in the previous lockloss.

Lockloss @ 03:06 UTC - link to lockloss tool

ETMX saw a small hit about a half second before the lockloss.

I made slow (ramp time = 120s) changes of the ITMY ESD bias today during observation mode in order to find a minimum in electronics ground noise coupling, using coherence between DARM and a current clamp on a grounding cable as the figure of merit. This project will continue, but I am done for the day and wanted to get today's times into the alog.

FAMIS 26444, last checked in alog78167

Both BRSs look good. The slight motion of BRS-Y looks to line up with small temperature changes.

FAMIS 26313, last checked in alog78597

CS fan 5 had a slight jump up in noise about a week ago, still well within range.

All other fans largely unchanged from last check and within range.

TITLE: 06/28 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: Two lock reacquisitions, both automated. Robert has been changing some ITM L3 biases while in observing, as approved.
LOG:

• 1601 Observing
• 1656 Lock loss
• 1843 Observing
• 2201-2202 Knocked out of observing while making SDF changes.