Tue Sep 30 10:09:27 2025 INFO: Fill completed in 9min 24secs

M. Todd

Summary

This morning I used the early maintenance day to come in and make some measurements of IMC DOF Transfer Functions to ISS Second Loop RIN. I started by doing some OPS/GRD settings as I was here about an hour before the operator was set to come in.

I got through the first DOF measurement (DOF_1_P) without any hiccups; however a 7.0 earthquake from Philippines came in an unlocked us. Fortunately, I did not have to wait long for the IMC to relock and I proceeded with the other measurements.

DOF 1 and DOF 2 are relatively robust, but upon starting the DOF 3 measurement I had to lower the gain even more than anticipated, as the 1 and 3 Hz resonances are quite strong. The first run at this unlocked the IMC. After clearing the IMC DOF 3 P history, I let the IMC relock (it was having trouble) and continued with the subdued measurements.

I also tried to measure the UGF of each DOF loop, but was nervous about injecting that hard at the frequencies I suspected would contain the UGF.

Later, I will post a comment that tries to map the quiet time IMC contributions to the ISS Outer RIN in the regions we have enough coherence.

List of Figures

1. DOF 1 P Measurement of IMC to ISS 2ND LOOP RIN
2. DOF 1 Y Measurement of IMC to ISS 2ND LOOP RIN 
3. DOF 2 P Measurement of IMC to ISS 2ND LOOP RIN
4. DOF 2 Y Measurement of IMC to ISS 2ND LOOP RIN
5. DOF 3 P Measurement of IMC to ISS 2ND LOOP RIN
6. DOF 3 Y Measurement of IMC to ISS 2ND LOOP RIN

[Tony, Erik]

We updated laptops at both end stations and looked for laptops left lying around.   We found one disconnected Zotac in the CER at EY and brought it back to the corner station as a spare.

FAMIS31407

Swapped the filters in the two chillers while they were running this morning. There was slight discoloration in both. The mesh diffusers/flow straighteners had some gunk buildup in them. I have some that should have arrived today that I will put in later.

[Tony, Erik]

We verified that the ETMX hardware watchdog started to count down when the connection from the satellite amps for ETMX was removed.

Bypass will expire:
Tue Sep 30 12:08:51 PM PDT 2025
For channel(s):
    H0:FMC-CS_FIRE_PUMP_1
    H0:FMC-CS_FIRE_PUMP_2
 

At the weekend, Ryan reduced the OPO Trans Setpoint form 80uW to 75uW. Today I used the SQZT0 SHG waveplates to maximize the power available to the Pump and then I minimized rejected HAM7 power. After doing these, with the OPO locked at 75uW, the OPO_ISS control mon is at 2.5V, it is unhappy normally when below 2.0V. I am able to lock the OPO with 80uW OPO trans setpoint, but the OPO ISS controlmon is at 1.4V so probably wouldn't last very long. Leaving with the 75uW setpoint. 

NLG as per 76542:

WP12814

Jim, Erik, Dave:

I have rev-locked built and installed Jim's new h1hpiham6 model. This is an internal ADC rewiring of 4 channels, no DAQ restart needed. We will restart the model later this morning when Jim completes his chamber side wiring work.

 TITLE: 09/30 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Earthquake
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: EARTHQUAKE
    Wind: 17mph Gusts, 14mph 3min avg
    Primary useism: 1.28 μm/s
    Secondary useism: 0.57 μm/s 
QUICK SUMMARY: Lost lock just a bit ago due to a 6.9 earthquake in the Philippines. Maintenance starting a bit earlier because of this. 

H1 Manager just called to tell me that we've been out of Observing for a bit. I know we recently bumped up the times for the Tuesday morning measurements to run, and that's why we're out of Observing, so I'm ignoring H1 Manager's call for help.

Workstations were updated and rebooted.  This was an OS packages updated.  Conda packages were not updated.

TITLE: 09/29 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:

Quiet shift with only a brief (& easy) drop from Observing due to SQZ.

Otherwise, locked the entire shift for a lock going on 21.75hrs (so no opportunities to shutt of Annulus Ion Pumps for HAM5/6).
LOG:

• 2339-2350 RyanC dropped by the VPW to check his tire pressure
• 0000-0011 SQZ lockloss & quick recovery (Camilla also left notes in mattermost if there was any troubles with the sqz and locking)

At the top of the hour (within 15seconds), the Squeezer unlocked and took H1 down.  Tony was in here and thought the timing was odd with it happening close to the top of the hour!  (he saw that the PMC went down at 00:00:15).  

The Log for the SQZ MANAGER also notes the PMC as the cause (w/ a message of "LO railing!").

I slowly got SQZ windows opened & got the wiki up and started recovery by Steps:

• #1:  Taking the SQZ MANAGER to DOWN.  Everything came back 
• #2:  Bringing back SQZ_PMC, SQZ_SHG, SQZ_OPO_LR and then SQZ_CLF_LR nodes all to their NOMINAL states
• #3:  This step is where I got a little confused.  The instructions say to take the FC node to GR_LOCKED (got there w/ no problem).  But then the instructions say:  "Trend H1:SQZ-FC_TRANS_C_LF_OUTPUT, if it's peaks are less than 100, follow instructions in below "Issues with SQZ_FC Guardian""."
  • Well, for me, this channel "flat-lined" at about 45-46 counts for GR_LOCKED (I did not see peaks), and this channel has been like this (under 100) for weeks (see attached).
  • So, I opted to NOT follow the Steps for Issues with SQZ_FC Guardian, and at this point, I just took the SQZ MANAGER to FREQ_DEP_SQZ, and this got squeezing & observing back.

TITLE: 09/29 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: We stayed locked the whole shift, 16 hours.
LOG:                                                                                                                                                 

• 15:31 - 18:35 UTC We dropped Observing to do some commissioning, including some PEM and SQZ tests.
• 19:21 - 21:21 UTC SEI to useism
• 20:06 UTC GRB-Short E605563
• 21:22 UTC Optics lab yellow 0.5 dust alarm

TITLE: 09/29 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 9mph Gusts, 5mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.41 μm/s 
QUICK SUMMARY:

Hand Off from RyanC with:

• Target Of Opportunity:  If H1 loses lock and a member of the VAC crew is here, let them know so they can climb on a chamber and adjust a valve.
• H1's been locked over 16hrs, with notes that locking has been straightforward (other than notes of SRM WD trips as of late).
• Seismically, primary µseism band is elevated (mostly just under the 95th percentile). 

• 18:22 The SQZ LO lost lock and struggled to relock and delayed the start of the calibration measurement
  • The first issue was the OPO not wanting to lock, following the wiki I started by cycling through DOWN
    • I restored FC2/FC1 alignments based on osems to when we locked the SQZer at the beginning of the lock, no dice
    • I maximized the H1:SQZ-SHG_GR_DC_POWERMON using  SHG_TEC_SETTEMP, accepted in SDF (36.05 -> 35.75)
    • It was still struggling to get a trans of at least 80, it would go right past it. It would get just over 80 then keep adjusting the ISS setpoint and the trans would decrease. I ended up changing the setpoint from 80 to 75 in sqzparams which got it locked.
  • Now the FC won't lock, the green trans is too low, I followed the wiki to maximize it
    • Restored ZM3, moved FC2 to maximize H1:SQZ-FC_TRANS_C_LF_OUTPUT, I couldn't get it above 50. Now it loses it at IR ("CLF frequency out of range")
    • I ran the SCAN_OPO_TEMP state and now it can lock IR
• 19:33 during the calibration measurement it lost lock again
  • The OPO keeps losing lock again. I maximized the SHG temp again, there was a suprising amount of gains still to be had (36.05 -> 35.05). Should I have done this again after running SCAN_OPO_TEMP earlier?
  • FCs not locking again, as soon as the calibration measurement finished it finally was able to hold green lock