TJ mentioned that it was reported that dust monitor 6 by HAM3 was giving weird looking data so I went out and tested it. I power cycled it, and testing it by rubbing my gloves above it and saw the counts increase. I also set up dust monitor 10 I believe, which was not being used, right next to it and set it up to take data and saw that both dust monitors were reading the same level of particles. I left both of thses dust monitors running next to HAM3.

Mon Jan 29 10:16:34 2024 INFO: Fill completed in 16min 29secs

FAMIS 20013

PMC transmitted power has been steadily dropping over the past 10 days, but RefCav transmission has been increasing. Both of these will be tuned up closer to when commissioning starts following vent activities.

TITLE: 01/29 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 0mph Gusts, 0mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.40 μm/s
QUICK SUMMARY:
No locking will be done today do to engineering run work.
 

Expected Engineering work today:
LVEA is still laser Hazard.
EX Pump Down will be started today.
ham 6 Work will continue.
Please be careful working at height due to local LASER HAZARD work near the SQZ tables.
Wind Fence work will continue.

 

Sun Jan 28 10:17:58 2024 INFO: Fill completed in 17min 54secs

Sat Jan 27 10:14:19 2024 INFO: Fill completed in 14min 15secs

OMCS was touching.
Rahul made OMCS transfer functions and found that something was touching. He, Koji and Betsy went to the floor to center the OSEMs. T1 was touching, which was fixed. Depth of OSEMs were adjusted, too.

Something is funny about OM3 damping.

Rahul also made TFs for OMs and thought that they were fine. However, OM3 PIT damping was oscillating at 1.75Hz. I flipped the sign of H1:SUS-OM3_M1_DAMP_P_GAIN (nominally -1, now +1) and it damped fine. I hate this.

1st attachment red shows the OLTF of OM3 P damping loop at around the offending resonance. This was of course measured with the flipped damping gain, and the OLTF looks absolutely strange. The 1st UGF is ~1.73Hz with -42deg phase, and the 2nd UGF is ~1.77Hz with -180deg phase.

If you draw a Nyquist diagram, you will find that this is a stable TF. OTOH, with the "correct" damping gain, this will become unstable. So we know why this works and why the correct sign doesn't, but we don't know what changed and why. 

Alignment converges.

With the OMC suspended without any biases, we adjusted OM1/2/3 biases to align the beam into the OMC (i.e. centering both of the OMC QPDs).

At some point we found that the ASC-AS_C was totally off-centered, used SRM to recenter, and continued the alignment.

2nd attachment shows the status as of now. Both of the OMC QPDs are reasonably centered, ASC-AS_C too. BOSEM DAC output for OM1 is ~11k max. OM2 and OM3 are at ~7k max  and ~9k max, respectively. These are OK though OM1 is not super.

Current status of the LVEA etc.

It's laser hazard. SQZ manager was set to DOWN. Koji closed small HAM5 GV and HAM7 -X curtain.

Remaining work (Monday).

• Fix the balance mass for OMCS.
• Check the beam positions on OM1, OM2 and OM3 (again).
• Adjust the WFS / OMCR paths.
• OMC trans video path?
• Restore the shroud panels.
• Restore the OMC trans beamdump on the -Y side.
• Check the centering on the irises on HAM6.

Rick and I cleaned the optics out here at End X.
Noted a drop in MAX Diffracted Power between M5 and the Wedged Beam Splitter from 1.1W to 1.08 W.
This may be due to the laser being turned off and not thermalized.

We would like to come back to End X and adjust the AOM alignment and we are leaving PCAL in a LASER SAFE status, LASER OFF and Key out.

Today's activities:
- HAM3 was prepared for door removal: the AIP was valved out, and the Annulus system was vented with N2
- EX was fully prepared for pumpdown, which happens next week
- RGA at EX was finished, it's totally leak tight - although its Ion-pump needs some troubleshooting
- There was a solution found for the filters' installation to the Hepta headers: the ISO-fitting will be done with a unique part (https://ancorp.com/product/4500060/), as the more standard claw clamps cannot be fit there
- The 2nd bellows for the relay tube was located - it needs class-A C+B
- Dew points were measured at the corner and at EX, all is good: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=75590

Marc, Erik, Corey, Betsy, Jim, Dave:

h1seih16 and h1oaf0 were power cycled to recover them from this afternoon's crashes. Sequence is (* applies to h1seih16 only)

1. stop all models
2. fence from Dolphin fabric
3. power down fe computer
4. * power down AI chassis
5. power down IO Chassis
6. power up IO Chassis
7. power up fe computer
8. * power up AI chassis

Everything restarted with no issues.

Jim has requested that no watchdogs be untripped on the h1seih16 system. The first DAC (HAM6 ISI+HPI) is still in its DACKILL state because the SWWD is untripped. The second DAC (HAM1 HPI) has zero drive because the h1hpiham1 model is untripped.

Latched IPC and DAQ-CRC errors have been cleared.

Replaced the Endevco Accelerometer Power Conditioners with LIGO Accelerometer Power Conditioners. WP11653

Order in the rack:

U19 - Accelerometer Power Conditioner S2300062

U16-U17 AA Chassis S1300101

U14 - Accelerometer Power Conditioner S2300063

U13 - Accelerometer Power Conditioner S2300065

U12 - Accelerometer Power Conditioner S2300069

U11 - Accelerometer Power Conditioner S2300064

Still have EX, EY, MX, MY, FCES to complete.

M. Pirello, J. Jimerson. R. Schofield

TITLE: 01/26 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

Afternoon shift's main item of note  is the CRASH of the OAF front end as well as the SEIH16 model; recovery of this would be made after the shift (after CER accelerometer work).

OMC aligning (from the Control Room) has also been ongoing through the afternoon by Keita/Koji/Rahul.
LOG:

• 2102 Tagging in for Oli's shift (corey)
• 2113-2151 MY part search (gerardo)
• 2123-2144 Hartman table checks (camilla)
• 2153 HAM3 baffle bolt assy prep in HAM3 cleanroom (mitch, tony)
• 2145-0000 Accelerometer work in CER (marc, jabari)
• 2207-2252 HAM3 vent prep (jordan, janos)
• 2223 OAF model crash (On CDS Overview, we have Front End & ADC faults/red, but also have issues with HAM SEI1/6 model [which is a surprise]).  Suspect this is due to the Accelerometer work in the CER.  Plan is to let Marc finish his work before starting front end recovery work.
• 2249 External Alert tests (tj)
• 2306-2329 Locking HAM3 HEPI (jim)
• 2307-2347 EX pump down prep (jordan)
• 2318 Grabbing ladder at EY (ken)

Measured the purge air dew point at the corner station during "lunch break", no people in chamber, measured -42.0 degrees C.

Travis measured the purge air dew point at EX, all ports closed, purge valve closed, no usage from vacuum volume.  Measured at purge valve area -41.3 degrees C.

Today's activities:
- The RGA tree at EX was leak-checked, and multiple flanges were leaky, possibly because of some overheating during a bakeout in the past. The gaskets will be redone, and the all-metal angle valve will be also replaced
- EX was vented
- The VPW vacuum chamber was opened, after the 2 stuck screw was removed
- Both 2 spare roughing stations are entirely finished
- All the Hepta header filter works were finished in the LVEA