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:
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
Summary of OMC-QPD profile measurement
Qualitative comparison of beam profile between single bounce (SB) beam and squeezer (SQZ) beam, arriving at the OMC-QPD. These measurement are done by comparing PIT and YAW response with OM3 movements. PIT and YAW response at around the center is expected to be inversely proportional to the beam diameter.
The valid data of each beam can be obtained
1) SB: 18:08:00 ~ 18:19:48 (UTC) -- with WFS centering on
2) SQZ: 20:12:00 ~ 20:18:00 (UTC) -- w/o WFS centering (mistake)
Since AS_C centering was off, it would be not perfect data, but judging from those measurement, SQZ beam is smaller than the SB beam. The
Below table is showing the relative ratio between SB and SQZ, with PIT and YAW individually.
| QPD A | QPD B | |
| PIT | 14.4% | 25.3% |
| YAW | 30% | 31% |
Added screenshots of comparison: 1) PIT comparison, 2) YAW comparison
Red lines are the plots that applied with the low-pass filter, and dashed lines are linear fitted lines in the range of (-1, 1) for both PIT and YAW.
Minhyo, Keita
As the PIT response on both QPD A and B are noisy, Keita and I checked for the source of that noise. By looking at multiple channel (1st screenshot), we found that ASC-AS_C PIT is also showing large noises.
Keita checked on the witness sensors of the mirrors before ASC-AS_C, and found out that beam splitter (BS) mirror is also showing large oscillation at around the SB measurement time (2nd screenshot). Checking with the ITMX(Y) status, it seems that BS is noisy after making single bounce (SB) beam condition.
After checking with the power spectrum data of SUS-BS_OPLEV_PIT_OUT_DQ (3rd screenshot), we noticed that the noise is higher during the SB measurement under 10 Hz, which is also showing large coherence with ASC-AS_C_PIT. We still don't know the exact origin of this noise, but it have definitely affected the beam's PIT movement beyond BS.
Minhyo, Keita
(Accidently didn't write alog about this, so I'm posting this in the comment)
We tried to measure the beam diameter that falls onto OMC-QPD (T1000276). The theory is to use the center gap of QPD as a calibration source, measuring the QPD SUM output data can give the information about the beam radius, since the power loss will occur due to the center gap in the QPD. It is expected that the SUM output will be minimum at the center, and gradually increase in respect to the offset from the center of QPD.
The measurement was done with single-bounce (SB) beam condition, during 2024-03-19, 18:30:00 ~ 19:30:00 (UTC). At first, we tried to center the beam by using SR2, AS_C centering loop and WFS centering. After that, tried to center the beam with using OMC servo with mastergain=0.1. The actual measurement time is in between 19:04:30 ~ 19:22:00 (UTC), and moved OM1 and OM2 manually, to move the beam off from the center (1st figure).
However, by checking on H1:ASC-OMC_A(B)_SUM_OUT16 channels, it didn't show the trend what we were expected. In almost all times, the power output showed consistent trend, and QPD A even showed highest value around the center of QPD (2nd, 3rd figure). Whereas, WFS sensor (AS_A and B) showed the expected increasing trend of power in respect to the offset from the center (4th figure), even though they are using same photo diode model.
From discussion, we suspect two origin for the descrepancy from the expected trend; 1) The center gap of QPD model (InGaAs-Q3000) is different from the cataloue (0.045 mm), 2) Quantum efficiency of QPD is not consistent in near the edge of each quadrant diode.
In conclusion, the quatitative measurement of beam profile of OMC using the center is limited due to the uncertainty of the QPD.
Attached figures are: 1) Visualization of the beam movement and power in each OMC-QPD, 2) Time series data of QPD channels, 3) OMC-QPD SUM_OUTPUT data in respect to the offset from the center, 4) WFS (AS_A and B), and AS_C OUTPUT data in respect to the offset from the center
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.
Issue is tracked in FRS 31005
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.
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:
| Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
|---|---|---|---|---|---|---|
| 16:42 | SQZ | Terry, Kar Meng | Opt Lab | LOCAL | SHG work | 19:04 |
| 18:58 | CAL | Rick | PCal Lab | - | Inventory | 19:03 |
| 20:29 | FAC | Tyler | MX | - | Check on contractor | 21:14 |
| 20:47 | SAF | Travis | FCTE | - | Dropping off laser glasses | 20:56 |
| 21:17 | SQZ | Terry, Kar Meng | Opt Lab | LOCAL | SHG work | 23:17 |
| 21:23 | ISC | Gabriele, Sheila, Jennie | CR/Remote | - | FF/A2L measurements | 22:00 |
| 21:40 | PEM | Robert | LVEA | - | Moving black glass guillotine | 21:45 |
| 00:23 | Health | Patrick | Mid Y | N | Walkign Down to MidY | 01:12 |
| 00:54 | PCAL | Mr. Llamas | PCAL Lab | N | Getting PCAL tools | 02:04 |
| 02:58 | PCAL | Mr. Llamas | PCAL lab | N | Plugging cable back in. | 03:08 |
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.
I reran the A2L script today during our small on the hop commissioning window.
The new gains have been entered in the guardian via the a2l_gains dictionary in userapps/isc/h1/guardian/lscparams.py
'FINAL':{
'P2L':{'ITMX':-0.9646, #+1.0,
'ITMY':-0.4071, #+1.0,
'ETMX':3.2767,
'ETMY':4.8886}, #+1.0},
'Y2L':{'ITMX':2.7253, #+1.0,
'ITMY':-2.0093, #+1.0,
'ETMX':4.7658,
'ETMY':0.9094 },#+1.0},# Centered on the optic #removed offsets from EY IX IY 220705 gm jd ec
}#spots that are the center of the optic
}#close a2l gains dict
and accepted in SDF in OBSERVE.snap, see attached images.
Jennie W, Sheila
The gains that changed the most were ITMX P2L (19%) and ITMY Y2L (17%).
Looking at the power spectrum before and after the A2L gain change and the SRCL feedforard update, DARM is the same above 14 Hz and below 8 Hz but shows slight improvement between these frequencies.
The bottom two rows of plots show coherences between DARM and angular degrees of freedom (middle row), and DARM and suspension pitch motion (bottom room). With old FF and A2L on the left, new on the right.
The only ASC DOF (two middle plots) that seems to have got worse is CHARD pitch, DHARD yaw is hard to tell as it sees the calibration lines between 10 and 20 Hz. Also the SRCL coupling to DARM got better confirming the new FF is working.
The limiting degree of freedom seems to be CHARD pitch now. Looking at the bottom plots, ETMY and ETM X pitch coherence with DARM have got worse.
There had been a suggestion (passed to me by Sheila) that we should measure the beam positions on SRM and SR2 after the big move that we made this week (which is summarized in alog 77427).
We don't have a premade script to do this like we have for the test masses, so I just did it by hand. One at a time, I put in a line using the ADS screen to SR2 or SRM pit or yaw, then changed the corresponding A2L element to minimize the line height in CAL-DELTAL_EXTERNAL. I was also watching SRCL_IN1 and SRCL_OUT, but the lines disappeared in the SRCL signals before they disappeared in the DARM signal, so I just used DARM.
All A2L values for SR2 and SRM had been 0.0, so I'm not going to bother putting in a 'before' column in the table below since they were all the same value of zreo.
After finding those values, I ran /opt/rtcds/userapps/release/isc/common/scripts/decoup/BeamPosition/CalcSpotPos.py to get from A2L coefficient to beam spot. This script had been made for IMC optics, but since SRM and SR2 are the same style, the calculation should be the same. Reminder of where this calc comes from (it's referenced in the script): alog 31402.
We don't have any 'before' measurements to compare to, but at least we now have some amount of information of where we are on these optics after the big move.
I'm pretty sure that these new A2L values can only be good, so I've accepted them in both safe and observe snaps for SR2 and SRM (see first and second attachments, only 2 rows per SDF table are accepted). These A2L gains for non-test mass suspensions are not under guardian control, so this should be good enough to keep them in place.
In the table below, the Cal-Deltal line reduction factor ends up really just being the ratio of the peak height in DARM before I started doing anything to that dof, and the noise level. To do a better job of measuring this, I would have had to increase my excitation amplitude, but that didn't seem important enough to do given the limited commissioning time we had.
| ampl [counts] of line at 30.5 Hz | A2L gain step size when minimizing | CAL-DELTAL line reduction factor | Final A2L gain | Inferred spot position [mm] | |
| SR2 P2L | 0.1 | 0.1 | 50x | +5.5 | 11.1 |
| SR2 Y2L | 0.1 | 0.3 | 45x | -4.5 | -9.1 |
| SRM P2L | 0.7 | 0.1 | 100x | -3.4 | -6.8 |
| SRM Y2L | 0.7 | 0.1 | 50x | +3.6 | 7.2 |
I don't have time right now to think through the whole left-vs-right sign convention (it's discussed in alog 31402), but it does look like we're rather 'diagonal' in the SRC now, since the signs of the spot positions are opposite for SR2 vs SRM (eg one positive P2L and one negative P2L means the beam is on opposite sides of center).
Anamaria, Sheila
About sign conventions:
This means that on SR2 the spot is 11mm above the rotation center and 9 mm in the negative X direction from the center. On SRM the spot is 6.8mm below the center of rotation, and 7.2mm in the negative x direction.
Sheila and Keita have recently found and fixed sign convention errors. Please see alog 78393 for the corrected interpretation of A2L gains.
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.
Sheila, Camilla. Relooked at the times from the original SQZ_OMC scan (04/16) to the checked alignment back to this scan last week (04/24): when we moved ZM5 to increase power on AS_C, the alignment onto AS_C gets much worse, plot attached. AS_A/B can;t be trusted as much as the OM3_P is different. Today we translated he beam in yaw to investigate this, alog pending.