Jennie W, Sheila, Minhyo

Summary: We tried to walk the beam on the OFI with SR2 and 3 and cannot find another 'good spot' at least with moves in yaw of the SRC cavity axis.

Today we set the IFO up in single bounce with 10W input and ITMX mis-aligned. Then we moved the sliders back to what they were before Jenne made changes to them on Wednesday

Then we stepped SR2 down in yaw in steps of about 0.6 - 1.0 uradians and compensated for this movement on AS_C QPD by moving SR3 down in yaw also to recentre. Eevery few steps we had to tweak the pitch of SR2 or 3 in pitch as well as pitch motions of the SRs are slightly cross-coupled with yaw motions on the QPD.

Jeff then pointed out we should be moving SR3 first, as this is the mirror closest to the OFI so I switched to moving this mirror first and then SR2 to compensate. We tried to move the same amount down on SR3 that Jenne moved. The power got worse on AS_C, only imrpoving when we were very mis-centred in yaw on this QPD so that is not a good reference.

See a zoomed in image of the steps in SR2 and 3 and the effect they had on ASC-AS_A_DC_NSUM and ASC-AS_C_NSUM.

From this it looks as though the power throughput to ASC-AS_C (anti-symmetric port) was maximum when we were well-centred on ASC-AS_C just after the first cursor before we had started walking the beam.

I think this suggests that there is no small burnt spot in this degree of freedom across the OFI surface that we can walk to the other side of and see our throughput improve.

However the beam looked cleaner at points when it was positive in yaw on the QPD - not sure if this was real or not.

After these moves we reverted back (first cursor) to the alignment sliders we had before Jenne's moves on Wednesday 24th and took an OMC scan.

Then we went back to the 'nominal' alignment from this morning (second cursor) before maintenance started and took another OMC scan.

Naoki, Sheila, Camilla

After the output alignment shift reported in 77427, we tried to revert SQZ to the last successful SQZ-OMC scan in 77515 but when we increased throughput, AS_C alignment was bad. Today we translated the beam to get good throughput on AS_A/B and AS_C and a centered beam on AS_C with OMC DC centering loop running. This was a move of ZM4 -1000urad, ZM5 -650urad in yaw as reported by DAMP_Y_INMON channels

• We reverted all alignment sliders (ZM4,5,6 OM1,2,3 SRM) and PSAMS to April 16th (leaving PSAMS at 7.5V/0.55V pre-77268).
• Naoki injected the same amount of SQZ SEED power as previous OMC-SQZ scan
• We translated in YAW by yawing ZM5 negative 50urad to increase AS_A power and then yawing ZM4 negative to bring the beam back centered to AS_C. Tried the positive ZM5 direction beforehand and it got worse.
• At 19:49UTC we turned on the OMC DC centering loops.
• We had god throughput at 19:59UTC and  moved until we made things worse at ~20:00UTC and then backed off.
• Total ZM4,5 changes attached, sdf's attached.
  • Before 1st t-cursor is moving from optimum in-lock sqz to April 16th OMC-SQZ alignment.
  • Between t-cursors is our translation. We moved ZM4 -1000urad, ZM5 -650urad. ZM4 is at 24,000 counts out of available 32,000.

Attached shows previous April 16th OMC-SQZ scan compared to during today's translation and how we left the ZMs:

• AS_C power is similar (new 373 vs old 385). Around ~3% percent lower, it almost seemed correlated with oscillations in YAW which isn't good as could suggest some yaw clipping remains.
• AS_A/B power is similar/increased,  AS_A (new 74 vs old 75) and AS_B  (new 80 vs old 75). They were not the same as each other similar but this can be explained by the AS_C being  0.2 to 0.4 off in PIT and YAW in the April 16th scan.
• Centered on all AS_A/B/C PDs.

We're not sure how this change will effect in-lock SQZ as Vicky had to make big changed in 77400  and we may have seen that good OMC scan alignment isn't good SQZ alignment?

Closes FAMIS 26299, last checked in alog 77457

Corner Station Fans (Screenshot 1)

- No notable increases in noise beyond threshold.

- Around 4.5 days ago, what looks to be a restart occured in all fans. Notably:

• MR_FAN3_170_1 and 2  slightly decreaased in noise
• MR_FAN6_170_1 slightly decreased in noise
• MR_FAN5_170_1 slightly increased in noise
• MR_FAN4_170_1 had a small noise hump (increase) but leveled out 2 days later.

Outbuilding Fans ( Screenshot 2)

- No notable increases in noise beyond threshold.

- MX_FAN1_370 still producing pulses of higher and lower noise (long standing feature since at least alog 76942 (April 3 2024)

- MY FAN 1 was turned on while FAN 2 was turned off. MX Fan 2 was turned on while FAN 1 was turned off. This is expected and logged through Tyler's WP 11819, which is the "Quarterly lubrication of Axivane fans".

This morning I came into the control room as the magnetic injections were finishing, and ran the a2l script while the charge measurements ran.

I did this because after Jennie Wright ran A2L yesterday afternoon it was not well tuned: 77495

When Jennie ran it yesterday, the coherence was over the threshold for all 8 gains, so all 8 were adjusted.  This morning I ran it and the coherence was below threshold for ITMX P2L and ETMY Y2L, so those were not updated.  I increased their amplitudes in the run_all_a2L.sh script, but as I was re-running the IFO unlocked due to the charge measurements.

The attached screenshots show how it changed the optics that it did run for, this is a large difference from the values that Jennie got yesterday.  Jennie W ran the script 20 hours into the lock, while I ran it 37 hours into the same lock, so these were both with a well thermalized IFO. 

It seems that there may be two problems we are facing with tuning A2L, one that our process doesn't seem to always work well to minimize A2L, and second that it seems that the values may be changing over the course of a lock.

Minhyo

Tried move the beam on OMC QPD using single bounce beam (ITMX misaligned). Changed OM3 PIT & YAW from 18:04:45 UTC (gps: 1398534729).
- Tried same task with OM3, with turning off ASC centering, OMC centering, started new from 18:21:00 UTC (gps: 1398536470).
 

After finishing with OMC QPD, reverted all settings with OM3 and then moved to OM2.
- Moved OM2 PIT&YAW to check ASC-AS_A & B. Finished at 18:35:00 UTC (gps: 1398537318)

Same job was done (moving OM3 -> OM2) with SQZ beam on OMC (from 20:12:05 UTC to 20:24:00 UTC, gps:1398543158-1398543858)

Screenshots (ndscope) are: 1) Measurement with single bounce beam, 2) Measurement with SQZ beam
 

Closes FAMIS 26507

All channels had switches in the last quarter (screenshot 1)

EX had considerably less switches up until March 8th. I looked at the alog for this time but found nothing in particular. (screenshot 2).

Since all channels have switched in the last quarter, no further action is needed (per FAMIS task instructions).

Maintenance activities have wrapped up (was extended by ~1 hour) and now starting an initial alignment. Robert will do an LVEA sweep shortly.

The LVEA remains Laser HAZARD.

I went to FCES this morning to try to troubleshoot the sort of busted H1 GS13 on HAM8. I suspect there is something going on with the cable or interface chassis, but it's not something I think I've seen before. I tried swapping cables at both the rack and the chamber, and whenever the corner 1 chassis was connected to the H1 sensor, the transfer function from the H1 CPS to the H1 sensor would be half the magnitude of the other two sensor pairs. ASDs also show the H1 GS13 has half gain when the corner 1 sensors are connected to the corner 1 chassis. However, when the H1 sensor was plugged into the corner 2 or 3 chassis, all three sensor pair tfs would have the same amplitude. I could repeat this consistently, didn't matter how I swapped the cables around, as long as the H1 sensor wasn't plugged into the correct chassis all the l2l sensor tfs would look normal.

Attached plot shows two sets of data I took during this period, red blue and light green are the normal config, dark green, pink and light blue are with the H1 sensor on the corner 3 chassis, H3 sensor on the corner 1 chassis.

I will talk to Fil, but maybe in a couple weeks we can try running a temp cable from the FC mezzanine to the chamber, and see if that changes anything.

Andrei, Camilla

We aligned the fiber polarization to minimize the H1:SQZ-SHG_GR_DC_POWERMON channel, following the instructions of Report 71761 on rotating the waveplates.

The reduction in monitor power is depicted in the attached screenshot (POWERMON_lesser_timespan.png), showing a decrease from 0.24 [a.u.] to 0.03 [a.u.].

The fiber currently in use (Fiber.png) is SM980-5.8-125 - Single Mode Optical Fiber, 980 - 1550 nm, Ø125 µm Cladding. As it seems from the figure POWERMON_large_timespan.png, power is unstable in the long term. We propose to change the fiber to PS-PM980 - 970 - 1550 nm PM Photosensitive Fiber, 0.12 NA, 6.6 µm MFD and to tightly fixate the optical cable on the optical table to furhter reduce polarization shift.

Naoki, Andrei, Camilla

We aligned the pump AOM and fiber following 72081.

We set the ISS drivepoint at 0V and measured the AOM throughput. The throughput was 34 mW/59 mW = 58%. We aligned the AOM and got 65 mW/69 mW = 94% throughput.

Then we set the ISS drivepoint at 5V and aligned the AOM to maximize the 1st order beam. The 1st order beam improved from 4.5 mW to 15.7 mW. The 0th order beam is 34.9 mW.

We set the ISS drivepoint at 0V and measured the AOM throughput again. The throughput is 51.7 mW/77 mW = 67%. Although the throughput is improved by 10%, we could not improve more than that.

Then we aligned the pump fiber. The H1:SQZ-OPO_REFL_DC_POWER improved from 3.4 to 3.7.

Minor leaks on the LN2 dewar tank/plumbing were repaired today during tuesady maintenance. Most leaks found during the LN2 tank inspection (report posted to Q2000008) were easily repaired by just tightening the connections. Joints were sprayed with liquid leak detector to confirm tightness.

The only leaks not repaired were on CP5 (Tank #8514377), leaks on the safety burst adapter. We put a wrench on the fitting and could only get ~1/16th of a turn. The threads have large amount of sealant making it difficult to tighten the fitting any more. I will ask for a quote from Norco to isolate the burst disk and repair the threads/leak.

Closing WP 11842

Tue Apr 30 10:06:05 2024 INFO: Fill completed in 6min 1secs

Gerardo confirmed a good fill curbside.

Following from BS camera reboot last night, this morning I found that ITMY (infra-red) camera was blue-screen. I also found that ITMY-Green was giving blue-screen images but its pixel-sum was changing. I rebooted both ITMY (h1cam23) and ITMY-Green (h1cam24) this morning. All three cameras are served by h1digivideo2.

TITLE: 04/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Preventative Maintenance
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 9mph Gusts, 6mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.21 μm/s
QUICK SUMMARY: H1 just lost lock at the end of in-lock charge measurements (SWAP_BACK_ETMX), ending a 38 hour lock. Maintenance activities have begun.

• Wind and microseism are low
• All other systems nominal

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

TITLE: 04/30 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY:
H1 is still locked and 30 hours.
Over the past 8 hour we have dropped from Observing twice for short durations due to SQZ_Manager and Camera_Servo Guardians.
We are currently Observing and intend to continue to do so until 1500 UTC.

LOG:

The Camera_servo Guardian, was getting stuck on Dither, Then it stalls.
More specifically ASC-CAM_YAW1_INMON is STUCK.

Which appears to be the BS (26) on h1digivideo2. Contacted Dave to restart the port that the camera is being provided Power Over Ethernet on.

While Dave is doing that Naoki is Running a Scan_SQZANG to optimize the SQZ angle.

Camera is now restarted and we are now in Observing!

TITLE: 04/30 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 9mph Gusts, 7mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.17 μm/s
QUICK SUMMARY:
H1 is still locked but we have fallen into commisioning due to the SQZ ISS Pump.
Looking at Alog 70050 I have requested LOCKED_CLF_DUAL_NO_ISS
I changed the opo_grTrans_setpoint_uW from 80 to 50...

Reloaded and then noticed that the comments said that 50 was too low. I was still reading comments when Naoki got onto TeamSpeak and saved the day.
He said that 70 may be appropriate but 50 is too low due to the SQZ system being tuned for 80. please see alog 72044 .

H1 Is back in Now back in Observing.



 

Sheila, Camilla, Jennie + CR

After Jenne got AS port power back with large SR2/3 yaw offsets in 77388, Sheila wanted to check we could get our SQZ beam back to the power levels we had during the SQZ to OMC scan in 77213 (~75 counts on AS_A and AS_B NSUMs).

We revered ZMs (alignment and PSAMs), SRM, OM1, OM2 to that scan time: April 16th 19:10UTC. But in the old alignment we can only see ~10 on AS_A AS_B NSUM, plot from Sheila attached. So something has changed in the alignment in the SQZ to OMC path too: SQZ, ZM4,5,6, OFI, SRM, OFI, OM1, OM2.

From this old OMC-SQZ scan alignment, by pitching ZM5 200urad (sliders) we could get back to 75 on NSUM plot (AS_AIR beam too low off camera). OR  by yawing ZM5 ~150urad (190urad on sliders/ 130urad on osems) we could get back to 70 on NSUMs plot (AS_AIR camera looks better). 

Reverting PSAMs back to nominal.