Our range and SQZ BLRMs were low in this lock compared to yesterday so after checking that our RF6 power H1:SQZ-CLF_REFL_RF6_DEMOD_RFMON was still high (Good NLG) after Sheila adjusted it last week. I adjusted the SQZ angle from 16:45 to 16:55UTC and 17:05 to 17:15UTC, this is currently allowed during Observing but tagging DetChar just incase. It's a little confusing that improving SQZ BLRMs decreased the H1 range, see attached. Started at 141deg, ended at 130deg, I think there's room form more improvement and something is off.
Before Tuesday Maintenance (first t-cursor) our SQZ BLRMs and range looked good.
After Tuesday Maintenance and before the SQZ angle change they were not goof, unsure what changed.
Since yesterdays SQZ angle change (2nd t-cursor) the BLRMs are better but are seem like the angle is not perfect as the BLRMs are reaching a minimum and then turning up after a few hours.
TITLE: 06/14 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 133Mpc
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 13mph Gusts, 9mph 5min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.17 μm/s
QUICK SUMMARY: IFO has been in NLN for 3h30.
Dust monitors, VAC, SUS, SEI, CDS all okay.
TITLE: 06/14 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 131Mpc
SHIFT SUMMARY:
Lock#1:
Lockloss at 07:41 due to PI29
Lock#2:
Yarm locked very nicely and quickly, unlike Xarm which went through increase flashes twice. Lost it at LOCKING_ALS (Xarm lost lock then Yarm). 2nd try locked als fine but couldn't get DRMI, went through PRMI and it took 2 attempts to lock. I tapped PRM in yaw by 6 microradians based on the AS_AIR image and it caught and stayed locked on the 2nd attempt, DRMI then locked quickly.
NLN at 09:00UTC, PI31 started to ring up almost immediately but was damped effectively by guardian.
In Observing at 09:08UTC
Another PI29 lockloss at 10:15
Lock#3:
Paused at DC_READOUT and let the PI DTT take a measurement, following the PI wiki to check and see if the mode had damped. Spent 20 minutes here before moving back up after not seeing any large peaks on the DTT or the 80kHz scopes.
NLN at 11:31UTC, in Observing at 11:39UTC
PI29 starting to ring up again at 12:54 (1:24 into the lock) but guardian succesfully damped it this time (yay!)
Handing off to Camilla
LOG:
No log for this shift
I looked at the "PI29" lockloss trends, with 2 unsuccessful and 1 damping successful-ish attempt. The channel for "PI29" damping looks at the DCPD output in a narrow band of ~5 Hz centered around 80.302 kHz. But it seems like the damping PLL now locks onto this new mode ~80.295 kHz, based on at trends of the damping PLL's frequency counter output. So, I'm wondering if this new mode causing locklosses is really at ~80.295 kHz, around 5+ Hz away -- if so, our damping PLL probably won't work. Looking around 80 kHz on the full spectrum DCPDs as the PI rings up, it looks like there are 3 narrow, distinct peaks between 80.295-300 Hz, so it's not crazy that there are additional distinct modes in the 80.3 kHz forest. The aliased-down 14.76 kHz monitor also sees this new problematic mode being several Hz off from where we're looking to damp.
Based on how the PI29 damping seemed correlated with "damping" it on the last attempt this morning, I think it'd worth trying a new PI damping path w/guardian for this new frequency, and on the same test mass, ETMX, though we'll only be able to fully confirm this by checking in full lock.
This is a followup on the previous analysis in 70134. In our disucssions we wondered if the low frequency excess noise can be all ascribed to the LSC feedforward being mistuned. The answer is: not all the noise increase, but only some of it.
The attached plot shows a selection of about 1500 times: each one is a period of at lest 600 seconds when the range was above 120 Mpc. For each segment I computed the average noise in the band 20-50 Hz as a proxy for the low frequency sensitivity. The gray circles uses CAL-DELTAL_EXTERNAL_DQ as in 70134. I then used a multi-coherence-based subtraction to remove the coherent contribution of LSC-MICH, PRCL and SRCL from DARM. This method should be similar to what Valera did and it's similar to the frequency-domain subtraction that NonSENS used to do. This "coherence-based subtraction" gives us an idea of the best that the LSC feedforward could ever do, by completely removing the coherent contribution of the LSC signals from DARM.
The orange dots in the plot show the 20-50 Hz noise after the coherence-based subtraction is performed. It looks like:
We've lost lock twice in a row from PI29, 1:30 (1st) into the lock and 1:15 (2nd) into the lock. Relocking has been fairly straight foward and automated. I'm currently waiting in DC_READOUT for the PI DTT to take a measurment to check on the modes damping, following the PI wiki.
Another PI29 lockloss at 10:15, I tried to help fight it by changing the phase but it was to no avail. We lost lock again less than 2 minutes from when the PI starting to grow. Lock time of 1:15
We lost lock at 07:41 due to PI29, the time from when the PI started increasing to losing lock was less than 2 minutes.
TITLE: 06/14 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 128Mpc
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 13mph Gusts, 8mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.13 μm/s
QUICK SUMMARY:
Taking over from Corey
TITLE: 06/13 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
SHIFT SUMMARY:
Shift mainly marred by high winds for about 6hrs of shift, but back to Observing during last hour of shift.
LOG:
Heavy winds continue and the green Y-Arm has trouble staying locked (I've stayed at LOCKING ARMS GREEN during the high winds).
Attached is a look at the last 3hrs zoomed in on speeds from 30-54mph. The last 90min have been highest thus far for the shift....but if I squint it might slowly be dropping...but we are still with gusts in the 40-50mph range.
TITLE: 06/13 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 25mph Gusts, 18mph 5min avg
Primary useism: 0.08 μm/s
Secondary useism: 0.11 μm/s
QUICK SUMMARY:
I might have re-saved my original post as a draft after I posted, so I lost my original post---reposting now.
wind, Wind, WIND!!!
Arrived to see H1 after a recent lockloss---Camilla mentioned the winds (I also drove through the gusts and eyed a fire in the Benton City area on the drive in as well.). We've also had a few gusts in the 40mph range in the last 30min.
Currently have OBSERVATORY Mode in the WIND state, have taken ISC LOCK to LOCKING ARMS GREEN, and holding here until the 60min timer alarms for a reassessment. This is because of the loop of losing lock at early states of ISC LOCK.
TITLE: 06/13 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 131Mpc
SHIFT SUMMARY: Easy relock after Tuesday Maintenance but the wind is forecasts\ to pick up this evening.
LOG:
There is a computer Patrick left turned on in the EY Mech room on HEPI pump controller, Robert powered off the monitor but said that he has previously done research that new style LED monitors are less nosy than computers.
| Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
|---|---|---|---|---|---|---|
| 13:14 | CDS | Erik | Remote | N | Restarting NUCs OPSLogin0 | 13:22 |
| 14:24 | FAC | Tyler | MidY | N | Slowly move snorkle lift to MidY | 15:10 |
| 15:00 | PCAL | Tony | PCAL lab then CER | N | PCAL measurement prep | 15:27 |
| 15:00 | FAC | Karen | EndY | N | Technical Cleaning | 16:01 |
| 15:07 | FAC | Bubba | Air Handler Room | N | Fans alog 70404 | 17:07 |
| 15:09 | VAC | Travis, | EX, MX | N | Monthly Turbo Pump Checks | 17:54 |
| 15:14 | FAC | Tyler | OSB Recieving | N | Forklift Move | 15:15 |
| 15:15 | COMM | Sheila, Jason | LVEA | N | PSL Racks - turn off sidebands | 15:25 |
| 15:16 | PCAL | Rick, Tony, Julianna | EX | YES | PCAL Measurement, WP 11253 | 17:40 |
| 15:17 | FAC | Kim | EX | YES | Technical Cleaning | 16:17 |
| 15:22 | PSL | Jason | CR | N | Touch up RevCav Alginment alog70402 | 16:12 |
| 15:23 | EE | Fil, Patrick | EY | N | New HEPI Beckhoff, Jim turned off HEPI | 19:06 |
| 15:31 | COMM | Sheila | CR | N | Prep for OMC scans and OMc scans (ETMs misaligned) alog 70409 | 17:44 |
| 15:36 | SEI | (Jim) | EY | N | EY HEPI offline | 19:17 |
| 15:44 | CDS | WAP | All buildings | N | WAP turned on | 19:17 |
| 15:50 | COMM | Daniel | LVEA/CER | N | PSL Racks turn off 117MHz sideband | 15:58 |
| 16:26 | FAC | Karen, Kim | FCES | N | Technical Cleaning | 17:19 |
| 16:29 | SEI | Jim | FCES | n | Feedthrough protection | 17:24 |
| 16:54 | EE | Marc | CER Mezz, EX, EY | N | Check on Kepco Power supplys (not in VEAs) | 19:04 |
| 17:40 | EPO | Mike + 12 | LVEA | N | Tour | 18:13 |
| 17:43 | VAC | Gerardo | FCES | N | length measurements - cables and pipes | 18:18 |
| 17:43 | COMM | Shiela | LVEA | N | Turn on RF sidebands | 17:54 |
| 17:45 | VAC | Janos, Jordan | LVEA, EY, EY | N | Labeling Equipment | 18:57 |
| 17:46 | OPS | Tony | EX | N | Dust Moniter Pump Replacement | 18:54 |
| 18:13 | Tour | Rick + 5 | LVEA | N | Tour | 18:55 |
| 18:26 | PEM | Robert, Bubba | EX | N | HVAC setup | 18:59 |
| 18:48 | SEI | Jim | CR | N | HAM4 TFs | 21:06 |
| 18:10 | SEI | Jim | EY | N | Assist with HEPI Beckoff | 18:40 |
| 18:00 | FAC | Kim, Karen, Cindy | LVEA | N | Technical Cleaning | 18:50 |
| 19:05 | PCAL | Tony | PCAL Lab | N | PCAL lab | 19:45 |
| 19:07 | PEM | Robert | EY | N | Get equipment | 20:02 |
| 19:24 | Betsy | LVEA | N | Walkthrough | 19:36 | |
| 19:31 | VAC | Janos, Jordan | Mx, MY | N | Lableing Equimpent in VEA | 19:58 |
| 19:40 | CDS | Dave | Remote | N | als retarts and DAQ restart | 19:40 |
| 19:52 | PEM | Robert | LVEA | N | Accelerometers near Oplevs | 20:12 |
| 21:03 | PCAL | Tony | PCAL Lab | N | PCAL | ongoing |
Went out of Observing due to SQZ-OPO_PZT_1 getting to edge of it's range 40-110V. No changes have been made to mitigate this as it only changed so rapidly as the LVEA temperature changed, see 70477.
Caused a deliberate Lost lock for Tuesday Maintenance at 15:08UTC (1370704124) alog70399
Relocking was uneventful. Prior to starting initial alignment (while other work was finishing up) I manually touched ETMs and TMSs for better green flashes and then completed an initial alignment.
The lock acquisition itself was completely automatic but we did loose lock twice (TUN_ON_BS_STAGE2 and OFFLOAD_DRMI_ASC). I expect this was due wind > 20mph, plot attached.
NLN at 21:14UTC, Observing at 21:25UTC. Brina accepted a sdf for alog70423: 4:1 Hz MICH1 FM3 filter.
Brina, Sheila,
After taking a look at the UGF for the Michelson loop, we turned back on the 4:1 FM3 filter on 06/13/23 at 21:17:50 UTC and will run it for at least a week to see if this aids in keeping lock from Earthquakes, (alog 70293 thread).
The original filter was in MICH2 FM3 (see 68432) (which is the same as what Brina and I edited MICH1 FM3 to be this morning), and was engaged in the DRMI guardian. I've edited and loaded the DRMI guardian to engage this again, so next time we relock this should be on.
This gets turned off when the IFO unlocks (in sdf revert). To keep this filter on in Observing, the operator should REVERT the lsc model sdf diff for MICH1 FM3 (turning FM3 on) to get into observing.
To get around this we could decide to keep this on during locking or editing the guardian.
WP11256 Upgrade EY HEPI Pump Controller to Beckhoff
Patrick, Fil, Jim, Dave:
Patrick and Fil installed the new Beckhoff HEPI Pump Controller at EY alongside the original "Ben purple box". The new unit has the temporary name h1hpipumpctrley1, Fil ran a new ethernet cable to it from sw-ey-aux port14.
Patrick and Fil got the new unit booted and on the network. Its EPICS IOC is running, there is no overlap in channel names between the old and the new EPICS databases, so they can run at the same time.
The new unit was not put into production today, we are still using the original unit to control EY pumps.
WP11245 TW0 raw minute trend files offload
Jonathan, Dave:
To complete last week's offload of raw minute trend files from TW0 SSD to h1daqframes-0 HDD, the hand edited daqdrc on h1daqnds0 was put into puppet by Jonathan. We verified the configuration when the DAQ was restarted today.
WP11254 Atomic Clock Re-synchronize with timing system
Daniel:
Daniel resync'ed the atomic clock. Please see his alog for details.
WP11257 Remove obsolete filter-modules-with-control parts from h1als[ex,ey]
Daniel, Dave:
Daniel downgraded the H1:LSC-X_ARM_DRIVE and H1:LSC-Y_ARM_DRIVE filter modules on h1als[ex,ey] to standard filter modules. This fixes the issue of the fm-w-ctrl having hardcoded Cin and Cmask attempting to turn on non-existent FM3 and FM5 filters.
Because the MASK PV for these FMs were removed from the INI files, a DAQ restart was required.
DAQ Restart
Dave, Jonathan:
The DAQ was restarted for the above h1als[ex,ey] model changes. Both GDS0 and GDS1 required a second restart to sync their channels lists, other than that it was a good restart and the DAQ configuration is consistently in puppet.
Tue13Jun2023
LOC TIME HOSTNAME MODEL/REBOOT
12:31:30 h1iscex h1alsex
12:32:00 h1iscey h1alsey
12:33:45 h1daqdc0 [DAQ] 0-leg
12:33:55 h1daqfw0 [DAQ]
12:33:55 h1daqtw0 [DAQ]
12:33:56 h1daqnds0 [DAQ]
12:34:03 h1daqgds0 [DAQ]
12:35:11 h1daqgds0 [DAQ] gds0 2nd restart
12:36:53 h1daqdc1 [DAQ] 1-leg
12:37:02 h1daqfw1 [DAQ]
12:37:03 h1daqnds1 [DAQ]
12:37:03 h1daqtw1 [DAQ]
12:37:11 h1daqgds1 [DAQ]
12:38:06 h1daqgds1 [DAQ] gds1 2nd restart
DAQ Frame File Channel List Change
Two slow channels removed from the DAQ Frame today (name, size-bytes, data-rate-Hz)
H1:LSC-X_ARM_DRIVE_MASK 4 16
H1:LSC-Y_ARM_DRIVE_MASK 4 16
Wrapping up Tuesday Maintenance. Main activities were:
The temperature swing shown in this aLOG is relatively small (~ +/-0.4 deg F), entirely explained by the maintenance day activities on the HVAC system, and recovered to 67 +/- 0.2 deg F by 17:00 PDT. See LHO:70428.
This morning Tyler, Chris and myself cleaned the strainer on coil 3 for the chilled water system. This strainer was not as bad as coil 4 which we cleaned 2 weeks ago. It did need cleaning and did improve the flow of the cooling coil. We plan to clean the other 4 strainers as time permits on Tuesdays. We also found the condensate drain plugged on AHU 1 again. We are working to unplug that drain now. The F/B damper on AHU 1 was closed completely so I have manually opened it to 70% for the time being to see if we can reduce some of the condensate from the coils. Coil 1 & 2 may need cleaning sooner than later if the condensate does not start going away soon.
AHU 2 Cooling Coil 3's strainer cleaning has had minimal impact on LVEA temperature value, nor fluctuations. Excellent! (Note, we've been calling these Fans, but I found out in talking with Bubba and Tyler today that this is a liquid strainer that filters the line that feeds the cooling coils. The *numbering* is still legit, they cleaned AHU2 Cooling Coil 4 strainer on May 30 2023 and today they cleaned AHU2 Coiling Coil 3 strainer) Separately, the change to have AHU 1 Damper at 60% is OK (Bubba had adjusted from 70% he mentions in his above aLOG to 60% shortly after posting; comments on its effect in the timeline below). After unplugging the drain of the air handler, and holding the damper open at 60% in "manual" mode (as opposed to servo controlled "auto" mode), the AHU 1 cooling coils 1 and 2 have now restored to much better/cooler, normal temperatures (~47 deg F) that we had lost by May 30th 2023 (the fateful fire-alarm chaos day; see timeline in LHO:70284). Excellent! LVEA temperature excursions in Zones 1A (this BSC2 / Beam Splitter), Zone 4 (Output Arm), and Zone 5 (Input Arm) never exceeded 0.4 deg F outside of 67 deg F range, and restored to normal ~67 deg F temperatures with small diurnal fluctuations within 7 hours. Excellent! Slowly but surely, I think these maintenance activities are good, and not only restoring expected system behavior, but making it better. We now have a much tighter collection of temperatures in the LVEA, cooling coils are operating at a nice low temperature, and more zone heaters are coming alive such that we have the expected "constant heat, constant cool in order to keep the LVEA temperature nice and controlled" behavior. I now have much more confidence that we can continue to do this kind of maintenance and not have it impact the IFO. Timeline of today's work all within today's Tuesday Maintenance: See Today's trend compared against a 7 day and 21 day trend. Jun 13 2023 08:26 PDT Bubba and Tyler start work, bringing down Air Handler 2, valving out AHU2's cooling coil 3's strainer and clean it. Understandably, all zones temperatures start to rise from 67 +/- 0.1 deg F but only max out 67.4 +/- 0.1 deg F. Also while out there, this is when they find that air handler 1 AHU 1 is flooded "again." Jun 13 2023 09:03 PDT Within a half hour, they're done with AHU2 strainer cleaning, AHU1 drain de-clogging, turn AHU2 back on, and temperatures begin to drop accordingly. Upon restoration, though, and back at the control room work station -- they still see AHU 1's cooling coil temperatures high (~ 61 deg F), as its been since May 30 2023. Indeed, also, the damper for AHU 1 is closed at 0%, as it has been doing diurnally since May 30 2023 -- the HVAC servo opens up AHU 1's damper each day (around when outside temperatures exceed 70 deg F), and then gradually ramps closed again by nightfall's temperature drop. Prior to May 30 2023, AHU 1 damper stayed around ~35% open throughout the day and night. Jun 13 2023 09:03 PDT Bubba intuits that there's too much condensation gathering in AHU 1 because its damper is closed too often, and that condensation doesn't get drained out because its drain is clogged. As a mitigation attempt, instead of having the HVAC servo drive the damper open percentage, he switches over to Manual mode and holds it at 70% as described in his aLOG. This drops both cooling coil's 1 and 2's temperature down from 61 to ~47 deg F. Awesome. But, this starts to scare the wimpy scientists (me) who are paying too close attention too quickly, because they see the temperatures in the LVEA drop below the 67 deg F set point. Jun 13 2023 10:02 PDT Zone 4 (input arm) zone heater turns on, and begins to bring the Zone 4 temperature back in line. Jun 13 2023 11:00 PDT Bubba makes a further adjustment of the AHU 1 damper percent open from 70% to 60% open to try to decrease the cooling in the LVEA. Jun 13 2023 12:07 PDT Zone 1A's zone heater collection turns on (human controlled? servo controlled?) for the first time, much like Zones 4 and 5 heaters came on for the first time after AHU2's cooling coil 4's strainer was cleaned, ramping up to ~70% in 5 minutes by 12:15 PDT. This really starts to turn around the LVEA temperatures for the better; the temperatures bottom out turn back up, overshoot a bit, and settle to yesterday's mid-day value. Jun 13 2023 17:00 PDT Temperatures are all restored within to ~67 +/- 0.2 deg F, and again, they never exceeded +/- 0.4 deg F. The "natural experiment" reveals the impulse response of the Zone 1A is about 5 hours, as long at the zone heater for that zone comes on!
This is an updated table reflecting all work that happened since Oct/2013 including our recent HAM1 incursion. The previous version from Oct/2013 is in alog 7844.
Systems, please update Optics BOM and the drawings in D1000313. Use attached as a reference. M18 needs to be newly added to D1000313 as it wasn't added when they installed REFL LSC_B sensor. M2, M12 and BDV2 need to be merely updated.
Bold font means that the information is not up to date in D1000313. Bold Italic with an underline means that the information in D100313 is not up to date AND it was installed/swapped in the latest incursion.
(Also note that there was a mix-up in the S/N in the old table. The optic we extracted from M2 had a serial number of 0944. In the old table, M2 was supposed to be 0990, OTOH 0944 was supposed to be M15. I don't know the S/N of M15 as of now but assume that it's 0990.)
| ID | Type and DCC | S/N or marking | Mount | Path etc. | comments |
| M1 | 2" 50% IR, E1000671-02 | ? | RH | REFL air-vac splitter. 2nd 50:50 common to LSC/ASC REFL path. | No change. |
| M2 | 2" 50% IR, E1000671-02 | ? | LH, V-dump behind. | REFL vac steering. 3rd 50:50 common to LSC/ASC REFL path. |
New. Used to be HR, E1100048 (ID 0944). AOI is large (larger than 50deg), reflectivity 41% in situ. alog 63544 |
| RM1 | 2" Curved +1.7m HR IR, E1100056-01 | ICS ASSY-D1001396-24 | HTTS | REFL vac MM TT1 | No change. |
| RM2 | 2" Curved -0.6m HR IR, E1100056-03 | ISC ASSY-D1001396-22 | HTTS | REFL vac MM TT2 | No change. |
| M5 | 2" Curved +1.7m HR IR, E1100056-01 | 3 | RH with dump | REFL vac MM fixed | No change. |
| M6 | 2" 50% IR, E040512-B1 (as opposed to E1000671-02) | IO824-01 on the barrel | LH with pico | REFL vac LS/AS splitter. 4th 50:50 common to LSC/ASC REFL path. | No change. |
| M7 | 2" HR IR, E1100048 | ? | LH | REFL air steering | No change. |
| M8 | 2" HR IR/GRN, E1000425 | ? | Peri wth dump | POP/ALS peri | No change. |
| M9 | 2" HR IR/GRN, E1000425 | ? | Peri with dump | POP/ALS peri | No change. |
| M10 | 2" HR IR, HT GRN, E1000669 | ? | LH | POP/ALS dichroic | No change. |
| M11 | 2" HR GRN, E1000652 | ? | LH with dump | ALS steering | No change. |
| M12 | 2" 95% IR, E1000671-v1-02 | ? | LH | POP vac/air splitter | New. Used to be 90:10 (ID IO820-09). alog 63523 |
| M13 | 2" HR IR, E1100048 | ? | RH with dump | PSL reference | No change. |
| M14 | 2" 90% S-pol IR, E040512-B4 | IO823-?? on the barrel | RH | REFL splitter for high power dump | No change. |
| M15 | 2" HR IR, E1100048 | 0990? | RH pico with dump | POP vac steering for LSC | No change. |
| M16 | 2" HR IR, E1100048 | 0965 | RH with dump | POP air steering | No change. |
| M17 | 2" 50:50 IR for P, E1000671 | ? | RH | 1st 50:50 common to LSC/ASC REFL path. | No change. |
| M18 |
2" 50:50 IR for P, E1000671 |
? | RH | LSC REFL A and B splitter. | No change. Doesn't exist in D1000313. |
| M101 | 1" HR IR, E1000595 | ? | 1" LH with dump | part of REFL WFS sled | No change. |
| M102 | 1" HR IR, E1000595 | ? | 1" LH with dump | part of REFL WFS sled | No change. |
| M103 | 1" 50% IR, E1000671-02 | ? | 1" LH pico | part of REFL WFS sled | No change. |
| M104 | 1" HR IR, E1000595 | ? | 1" LH pico with dump | part of REFL WFS sled | No change. |
| L101 | 1" f=+334mm, E1000845-03 | ? | 1" lens | part of REFL WFS sled | No change. |
| L102 | 1" f=-167mm, E1000845-08 | ? | 1" lens | part of REFL WFS sled | No change. |
| L1 | 1" f=+222mm, E1000845-02 | ? | 1" lens | for LSC REFL | No change. |
| L2 | f=+334mm, E1000845-10 | ? | 2" lens | for LSC POP | No change. |
| BDV1 | HR IR, old iLIGO | N/A (no marking) | BDV | for REFL air | No change. |
| BDV2 | HR IR, E1000048 | 2.0-0947 | BDV | for POP air | No change. alog 45279 |
| HW1 | 1" IR half wave plate from ALS stock | N/A (no marking) | rotator mount | for REFL |
No change. |
The IIET tickets that are open to address the "DOCS_NEEDED" call for help in this alog are:
IIET:11724 ECR: Second REFL LSC RF Photodetector
IIET:23545 Attenuate light on in-vac ISC sensors in HAM1