Full shift report can be found here: https://wiki.ligo.org/DetChar/DataQuality/DQShiftLHO20231023

Highlights:

• Spent an average of 70% of each day in observing, consistentlly around a range of ~150-160 Mpc. 
• Most locklosses seemed connected either to earthquakes or commissioning 
• Continuing to see periodic bursts of noise around 32 Hz that was noted in last week's DQ shift. It occurs on the order of a few times per day and seems connected to ground motion (potentially also being seen in floor accelerometers). See Beverly's alog for a more detailed explanation
• Starting Wednesday, some short duration low-frequency combs would show up on the order of a couple times per hour. On the spectrograms, it appears to be about harmonics of 4 Hz which could the noise that was noted early in O4 from EX's undamped cryobaffle (see alog) 

STATE of H1: Observing at 157Mpc

• We've been locked for 5:41, in observing since 23:28UTC

I went to look and see if the changes we did to the Picket fence, like using the PNSN and NEIC networks has impacted our ability to see earthquakes before they arrive to the site and the results are promising with the small sample I grabbed. So, once again thanks to the folks at NEIC and PNSN for helping set up the lower latency connections.

I went to the summary pages and looked for times that the SEI_ENV state changed to 'Earthquake' to make this list, I presume those are the earthquakes we would've liked to act on anyways and later we can do a more in-depth analysis. There are 6 events between Oct 26th and 30th and they are all listed in the powerpoint attached.

Main (preliminary) takeaways:

- When the events come from far away (and we have a SEISMON alert), it seems like the earthquke mode is triggered at 400 nm/s of peakmon ground motion. There are 4/6 examples where the picket fence would provide a warning time longer than 25 seconds. The exact numbers are 25, 63, 102, and 137 seconds of extra time if we leave the trigger at 400 nm/s. This is in line with the main purpose of the picket fence: To provide accurate estimates for teleseismic events.

- The picket fence would have given a 25 second forewarning for the EQ from northern BC mentioned in LHO aLog 73786. This indicates that the PNSN seems to be working with the low latency we expect.

- There is one 'outlier' events, a very small EQ that did not trigger the picket fence, but no lockloss happened [see slide 5].

- There is also a local EQ mentioned in LHO aLog 73756.  The local event triggers EQ mode when peakmon nears 600 nm/s, and it shows on the picket fence with enough amplitude about 7 seconds later. We still need more data to see how effective the pickets can be at warning about local events. This would be a nice bonus if we could use it effectively.

Naoki, Camilla, Sheila

Today we saw bad high frequency squeezing we recently have at the beginning of the lock as reported in alog73798. We reverted the CARM gain to nominal today, so the bad squeezing is not related to the CARM gain. We could recover high frequency squeezing by rotating the sqz angle, which means the sqz angle was not optimal at the beginning of the lock. However, the squeezing level was less than 4dB even after sqz angle optimization. We suspect that this worse squeezing level is related to ZM alignment change we recently had.

The first attached figure shows the ZM4/5/6 alignment for the past 9 days. We had 4.4dB squeezing a week ago, but ZM4/5/6 alignment changed 6 days ago during SQZ-OMC mode scan in alog73696 and we cannot recover 4.4dB squeezing after that.

We turned off SQZ ASC and walked ZM4/5/6 sliders to maximize the rms of ADF at OMC transmission with anti squeezing. The second attached figure shows that we could recover 4dB squeezing after ZM alignment change. To recover 4.4dB squeezing, we would need to revert the ZM4 alignment to the values a week ago. 

The DIFF beatnote looks to be pretty stable over the past 5 months, the COMM beatnote has fluctuated more, and looks to be decaying over the past 10-20 days.

There was a glitch seen in 2 of the scopes that corresponds to Tuesday maintenance.

Cooling: CB2 temperature is fluctuating more than it usually does and the CB1 temperature fluctuations are higher than they usually are, by almost a factor of 2 (~half a degree to a full degree).

Laser Trends: The laser room, anteroom, chiller room, and diode room RH channels have dropped significantly over the past week. All the room temperature fluctuations have increased as well.

Environment: AMP1_LD{3,4} have dropped a bit over the past week.

Stabilization: The FSS_TPD power has decayed rapidly over the past 4 days as seen by the "RefCav transmission is low" DIAG_MAIN notification. The PMC_REFL power was slightly stepped down last Tuesday, the 24th.

Oli Patane, Jeff Kissel

We are working our way through a development plan(T2300376) for the new O5 A+ suspensions (specifically HRTS, HATS, and BBSS). We recently were able to finish creating Simulink model library parts, which can be found in /opt/rtcds/userapps/release/sus/common/models.
We created new library parts for use within the new suspensions as well as generic suspension library models that will be used for testing and production.

Library parts for use within suspension models:
SIXOSEM_HF_WD_RMS_MASTER.mdl [link][img1] - basically an update of SIXOSEM_F_WD_AC_MASTER.mdl
    - BLRMS model part similar to the ones used for OPOS and OFIS
    - Will replace the OSEMAC module in the new suspension libraries
    - Similar version was made for a four OSEM stage in 2021 by Jeff - FOUROSEM_WD_RMS_MASTER.mdl

SIXOSEM_HF_STAGE_MASTER.mdl [link] - basically an update of SIXOSEM_F_STAGE_MASTER.mdl
    - Removed WDBLOCKFLAG because it is no longer needed
    - Replaced OSEMAC with OSEM HF AC from SIXOSEM_HF_WD_RMS_MASTER.mdl

New suspension library models:
HRTS_MASTER.mdl [link][img2]
HRTS suspensions only have OSEMS on M1, and those OSEMS follow the layout standard of F1 F2 F3 LF RT SD.
    - Uses SIXOSEM_HF_WD_AC_MASTER.mdl for M1
    - Doesn't need BIO switching
    - Doesn't need LKIN

HATS_MASTER.mdl [link][img3]
HATS suspension has OSEMS on M1 and M3, with the M1 OSEM layout matching HRTSs' and the M3 layout being the standard four OSEM configuration.
    - Uses SIXOSEM_HF_WD_AC_MASTER.mdl for M1
    - Doesn't need BIO switching
    - Does use LKIN
    
BBSS_MASTER.mdl [link][img4]
BBSS has six OSEMS on M1, and four each on M2 and M3.
    - Uses SIXOSEM_HF_WD_AC_MASTER.mdl for M1
    - Has BIO switching

TITLE: 10/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY:
LOG: Currently finishing some SQZ commissioning while LLO is down. Today we have backed out the CARM gain change 73844.

Had a lockloss at 19:42UTC 73843. Some EY temperature excursions today 73835 73841 that are now back to nominal. ITMY mode 5/8 violins have needed different damping settings 73845.

TITLE: 10/30 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Comissioning
OUTGOING OPERATOR: Camilla (DAY)
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 6mph Gusts, 5mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.43 μm/s
QUICK SUMMARY:

• We're wrapping up comissioning for the day shortly and plan to be in observing all night
• Temperature swings look like they've recovered
• All systems look good, PSL is still saying RefCav transmission is low

FAMIS25962

The script reported that ITMX ST2 H1, H3, V1 noise was elevated. These are definitely above the reference, but seem to be that way last check as well, and one or two before that. Alll others look normal.

After IFO in NLN for 9h14. 1382730139.

No obvious reason why, no 73818 DARM glitches before this lockloss. Secondary useism is high at 0.40 μm/s.

STATE of H1: Observing at 157Mpc. IFO locked for 8h30.

Rode through an EQ at ~16:20UTC. Had SRM saturations at the EQ time.

Microseism is increasing, plot attached.

The facilities team have worked to fix an issue with the AC at EY 73841 so we've had some EY temperature excursions that should be returning towards normal over the next ~hours, plot attached.

ADS taking more time to converge than it used to before switching to camera servos and going into Observing. Used to be ~15 minutes, this weekend taking up to 24 minutes. 

Ryan, Austin and Ibrahim looked into this in 69601 but didn't come to any conclusions. TJ said that high microseism increases time to converge and microseism has been increasing but was not high 28th/29th Oct.

Time between arriving in NLN and ADS switching to camera servos:

• 28 Oct
  • 06:03UTC - 21m
  • 19:15UTC - 21m
  • 22:52UTC - 20m
• 29 Oct
  • 02:51UTC -24m
  • 06:59UTC - 23m, attached
  • 12:04UTC - 23m
  • 17:52UTC - 23m, attached
• 30 Oct
  • 10:26UTC - 23m

Closes FAMIS#26436, last checked 73177

BRS Driftmon values are looking good and are well within range for both BRSX and BRSY, although there has been a very slight trend downward in BRSX Driftmon over the past week, possibly related to the temperature drifting this past week, which can be seen in both ETMX and ETMY.

We found that the temp in EY was not holding steady over the weekend. The heating coil for the space was commanded on but was not running. After investigating, we found that the line voltage fuse in Phase C had blown which was keeping the variable transformer from operating. We took the variable transformer out of the circuit and swapped fan relay contacts to run the elements not controlled by the variable transformer. Heating elements are currently working and EY is slowly heating up. The heating elements controlled by the variable transformer will need to have their resistance checked for a short or an open circuit during the maintenance window. 

Jenne notes that this changing high frequency noise during the first hours of a lock since Wed 25th Oct (purple trace in 73798) may be caused by the new higher CARM gain 73738, changed on that day.

In 73798, I noted The 4.8kHz noise that suddenly changes ~ 1h40 into NLN,  Jenne suggests this could be aliased down CARM gain peaking. Looking at the 64kHz channel, plot attached, noise disappears from 18.4 to 18.7kHz (v. large peak) and appears at 16.6kHz to 16.8kHz and at 21.1kHz.

We have had a weekend of shorter (~5hour) locks and two locklosses form LASER_NOISE_SUPPRESSION state#575 (73787, 73831), the state this CARM gain is changed. Maybe this gain change has made us less stable, we'll discuss today reverting it.

TITLE: 10/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
OUTGOING OPERATOR: Austin
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 2mph Gusts, 1mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.47 μm/s
QUICK SUMMARY: IFO been in NLN for 4h40

High Pitched Fire Panel alarm in the CUR was on 15:58 to 15:00:45UTC as the FAC team worked with the fire system. Tagging DetChar

ITMY mode 5 and 8 are not damping so I will try turning gains to zero, plot attached. 73826. Tagging SUS.

I activated Jenne's DARM2 boost from LHO:73745 (in FM2) at 10/27/2023 13:25:54. The FM2 change has been saved in SDF.

The file that includes this new DARM2 boost filter is at /opt/rtcds/lho/h1/chans/filter_archive/h1omc/H1OMC_1382307261.txt. I've copied it to /ligo/svncommon/CalSVN/aligocalibration/trunk/Common/H1CalFilterArchive/h1omc for the Cal group. The file has been committed to the SVN. The corresponding repo has been updated on the LHO cluster under the cal account too.