Wed May 01 10:13:10 2024 INFO: Fill completed in 13min 6secs
Gerardo confirmed a good fill curbside.
https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1398618745
PRM and SR3 saturations before the lockloss, 2.5 hours into the lock so we still haven't been able to take a thermalized calibration measurement. The only invasive/potential LL causing work going on was some PEM tests by Robert.
TITLE: 05/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 4mph Gusts, 2mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.13 μm/s
QUICK SUMMARY: Just got back into Observing after a lock loss, fully auto relock. Planned commissioning today from 9-12 PT
After yesterday's SQZ realigning 77530 we're nearly back to the squeezing levels we had before the output arm alignment shift 77427: 4.3dB above 1kHz, 3.3dB ~350Hz. Plot attached.
I made a small change to verbal_alarms tests in test.py to ignore the TEST node being in error as I plan on creating another state to test/learn some camera stuff and I don't want to annoy everyone in the CR with it going into error. Verbal alarms could use a restart to reflect these changes.
TITLE: 05/01 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: We are Observing and have been Locked for 1.5 hours. Overall quiet night with two almost fully automated relocks. Reminder that LVEA is still Laser Hazard
LOG:
LVEA is still in LASER HAZARD
22:49 Detector Locked for 52 mins and just got into Observing
22:50 Lockloss after 1m 14s Observing
22:56 Lockloss at LOCKING_ALS
23:08 Lockloss from TRANSITION_DRMI_TO_3F
23:49 NOMINAL_LOW_NOISE
23:52 Observing
03:35 Superevent S240501an
04:34 Lockloss
04:49 Lockloss from TURN_ON_BS_STAGE2
05:38 NOMINAL_LOW_NOISE
05:40 Observing
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
23:07 | VAC | Jordan, Janos | EY | n | Turn off pump | 23:26 |
23:46 | Betsy, Brian OReilly | MY | n | Approved activity | 00:46 |
05:40 Observing
Have been Locked and Observing for almost 4 hours, and just got a notification about superevent S240501an
TITLE: 04/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Busy maintenance day, but the initial alignment and lock acquisition that followed were straightforward. Lost lock shortly after starting to observe.
The LVEA remains Laser HAZARD for more potential viewport tests during commissioning time this week.
LOG:
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
14:30 | FAC | Chris, Tyler | MX, MY | - | HVAC fan greasing | 15:35 |
15:00 | CAL | Jeff | LVEA | - | HAM6 racks | 15:45 |
15:01 | FAC | Kim, Karen | FCES | - | Technical cleaning | 15:33 |
15:03 | FAC | Mitchell | MX | - | Grabbing case | 15:18 |
15:10 | VAC | Gerardo | MX, EX | - | Turbopump checks | 17:40 |
15:11 | SAF | LASER HAZARD | LVEA | YES | LVEA is LASER HAZARD | Ongoing |
15:13 | SAF | TJ | LVEA | YES | Transition to HAZARD | 15:19 |
15:15 | FAC | Eric | MER | - | Heating coil maintenance | 17:22 |
15:16 | ISC | Sheila, Jennie, Minhyo | CR | - | Single bounce measurements | 20:40 |
15:18 | VAC | Jordan, Janos | All | - | CP tank repairs | 17:05 |
15:18 | VAC | - | EY | - | Dewar jacket pumping | 17:05 |
15:22 | ISC | Jenne +1 | LVEA | - | Tour | 15:50 |
15:26 | IAS | Jason, RyanC | LVEA | - | FARO surveying | 18:46 |
15:28 | SAF | Travis | All | - | Captial inventory | 16:56 |
15:33 | FAC | Karen | EY | - | Technical cleaning | 16:30 |
15:33 | FAC | Kim | EX | - | Technical cleaning | 17:21 |
15:34 | SEI | Jim, Mitchell, TJ | LVEA | - | Craning 3IFO storage container | 17:15 |
15:35 | FAC | Tyler | OSB Roof | - | Inspection | 16:00 |
15:37 | PEM | Robert, Anamaria | LVEA | YES | Beam hunting (VIEWPORTS OFF) | 20:09 |
15:51 | FAC | Ken | FCTE, LVEA | - | Cable tray installation | 19:02 |
15:51 | SAF | Fil | All | - | Interlock checks | 18:35 |
16:01 | FAC | Tyler | EX | - | Checking for bees | 17:22 |
16:02 | CAL | Jeff | LVEA | - | Getting SR785 data | 16:07 |
16:41 | SQZ | Camilla, Naoki, Andrei | LVEA - SQZT0 | YES | Adjust SHG pump AOM/fiber | 18:10 |
17:21 | FAC | Karen, Kim | LVEA | - | Tech clean | 18:45 |
17:22 | FAC | Tyler | OSB roof | n | Checking roof status | 17:28 |
17:40 | VAC | Gerardo | LVEA | - | Capital inventory | 18:52 |
17:44 | ISC | Sheila | LVEA | - | Turning off sidebands | 17:50 |
17:52 | SEI | Jim | FCES | - | Troubleshooting HAM8 GS13 | 18:56 |
18:15 | IAS | Tyler | LVEA | - | FARO surveying | 18:40 |
18:49 | SUS | Jason | LVEA | YES | Troubleshooting ITMX oplev | 18:59 |
19:00 | ISC | Sheila | LVEA | - | Turning sidebands back on | 19:04 |
19:37 | SQZ | Terry, Kar Meng | Opt Lab | LOCAL | SHG work | Ongoing |
19:52 | VAC | Gerardo | MY | - | Capital inventory | 21:09 |
20:12 | FAC | Ken | FCTE | - | Electrical work | 21:12 |
20:20 | PEM | Robert, Anamaria | LVEA | - | Cleanup & sweep | 21:39 |
20:00 | CDS | Dave | EX, EY, CER | - | Looking for laptops | 20:54 |
Lockloss at 04/30 22:50 UTC from unknown cause
23:52UTC Observing
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 150Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 8mph Gusts, 6mph 5min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.23 μm/s
QUICK SUMMARY:
Have been Locked for 52 minutes and just got to Observing
Jennie W, Sheila
Today we took OMC scans to help diagnose what is going on with our alignment through the OFI - that is, what is the mode-matching at our the old alignment (as of Monday 22nd) and our new alignment (as of this morning).
Sheila turned off the sidebands before the test and we had the ETMs and the ITMX mis-aligned initially for single bounce configuration.
Old alignment: SR3 M1 YAW OFFSET = -125 microradians
SR3 M1 PIT OFFSET = -437 microradians
SR2 M1 YAW OFFSET = -421 microradians
SR2 M1 PIT OFFSET = -64 microradians
Due to PEM measurements we switched from single bounce off ITMY to single bounce off ITMX.
Locked time = 1 minute from GPS 1398534847
Unlocked time = 1 minute from GPS 1398534984
Scan = 200 s starting at 1398535070 GPS
New alignment: SR3 M1 YAW OFFSET = 120.2 microradians
SR3 M1 PIT OFFSET = 437.9 microradians
SR2 M1 YAW OFFSET = 2061.7 microradians
SR2 M1 PIT OFFSET = -5.5 microradians
Locked time = 1 minute from 1398538330 GPS
Unlocked time = 1 minute from 1398538461 GPS
Scan = 200 s starting at 1398537927 GPS
Dark time with IMC offline and fast shutter closed = 1398538774 GPS
Mode mis-match measurments pending...
The loss through the OMC appears to have increased after whatever happened to the output path on April 22nd.
I use again Sheila's OMC loss calculation code as we previously used in this entry.
Power on refl diode when cavity is off resonance: 29.698 mW
Incident power on OMC breadboard (before QPD pickoff): 30.143 mW
Power on refl diode on resonance: 5.153 mW
Measured effiency (DCPD current/responsivity if QE=1)/ incident power on OMC breadboard: 56.5 %
assumed QE: 100 %
power in transmission (for this QE) 17.029 mW
HOM content infered: 14.415 %
Cavity transmission infered: 66.501 %
predicted efficiency () (R_inputBS * mode_matching * cavity_transmission * QE): 56.494 %
omc efficency for 00 mode (including pick off BS, cavity transmission, and QE): 66.009 %
round trip loss: 3495 (ppm)
Finesse: 335.598
We compare these values to that found from our scans on the 16th April and it seems like the HOM content has increased substantially, the incident power has decreased, and the measured and predicted cavity efficiency has decreased by 3%.
It would be good to cross-check these figures against the other methods of checking the losses, such as DARM offset step and the mode mis-match I still need to calculate from the mode scan taken on the same day.
I forgot to run the same analysis for the locked and unlocked measurements we got at the old (pre April 23rd) alignment of SR2 and SR3.
Power on refl diode when cavity is off resonance: 25.306 mW
Incident power on OMC breadboard (before QPD pickoff): 25.685 mW
Power on refl diode on resonance: 5.658 mW
Measured effiency (DCPD current/responsivity if QE=1)/ incident power on OMC breadboard: 54.1 %
assumed QE: 100 %
power in transmission (for this QE) 13.885 mW
HOM content infered: 19.870 %
Cavity transmission infered: 67.970 %
predicted efficiency () (R_inputBS * mode_matching * cavity_transmission * QE): 54.061 %
omc efficency for 00 mode (including pick off BS, cavity transmission, and QE): 67.467 %
round trip loss: 3289 (ppm)
Finesse: 339.266
Robert, Jason, Anamaria
Today we used the oplev to determine the CP alignment for both ITMX and ITMY. We had to move the sender around to find all the beams so here I mark the shift in the beam location in case someone later wants to look at drifts. The ITMs were realigned slightly after our test so it's not good to 1urad but the oplevs drift around more than that anyway. I also had to choose times after lockloss and before relocking, to not have ASC interfere.
ITMX P | ITMX Y | ITMY P | ITMY Y | |
Before | -8 | -1 | -20 | 1 |
After | -10 | 5 | 6 | 2 |
Since people don't open the receiver box or the sender box very often we note:
a) The beams on the oplevs are as large as the QPD which is not great, but depends what they're used for.
b) We found the ITMX oplev beam to be clipping on the nozzle baffle. Jason helped us shift the QPD and then we realigned to this new, more central location.
c) Replacing the sender cover is very difficult without causing a shift in the oplev beam, though we were quite careful to not touch the telescope while doing that. This is why we were not able to center them better.
d) I suppose the last few urad should be done with the QPD stages, but one has to be careful to check from time to time that it doesn't walk out of the aperture over time (which is smaller since the installation of nozzle baffles).
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
Attached shows previous April 16th OMC-SQZ scan compared to during today's translation and how we left the ZMs:
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?
Naoki, Sheila, Camilla
This alignment didn't give us good in-vac SQZ.
We tried taking SQZ sliders to before the output arm alinement shift when we had these PSAMS (2024/04/17 23:38 UTC) with the addition of the -1000urad, -650urad offsets on ZM4 and ZM5. This made SQZ worse.
We moved ZM6 to maximize RF3 and RF6 adn then went to anti-sqz and ran SCAN_ALIGMENT_FDS twice. SDFs attached.
Naoki adjusted the SQZ angle to squeezing and reran SCAN_SQZANG, this got us back to 4+dB of SQZ and over 150MPc of range, still room for improvement but much better than last week.
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.
Another picket fence issue at 03:37 UTC, I think the third in the past few weeks. I restarted the process on nuc5.
Thank you for this summary. I will go dig in the code to see what is happening.
On first glance: the array of data should never be empty on an update, but somehow it is happening some times. I will add a failsafe (or an assert) so that the code can handle this exception and hopefully be more robust.
There was a drop in clean range around 5:20 this monrning, which doesn't seem to be a reapeat of the output arm shift we had earlier this week.
Attached is a trend of the DARM blrms (based on DARM error, no calibration corrections or cleaning) and comparison of the cleaned and corrected range against the CAL-DELTAL range, only the cleaned channel sees the drop. This made me concerned that we had a drop in optical gain, but the trend of the time dependent calibration correction factors doesn't show anything happening at this time.
I don't know what would cause a sudden change in the clean range, since I don't think that the jitter subtraction would cause a sudden change like this.
I'm still not at all sure why this drop happened, particularly if Sheila notes that there were no changes in the calibration TDCFs. However, the drop is seen in all of the GDS-CALIB_STRAIN channels, not just a drop in the _CLEAN channel. This indicates that the range drop comes from earlier in the process than the line subtraction or the cleaning.
The crosshair in the attached plot is the same time as the crosshair in Sheila's plot, just to make it a little easier to orient and compare the plots.
Blue: Range from CAL-DELTAL_EXTERNAL
Green: Range from GDS-CALIB_STRAIN
Red: Range from GDS-CALIB_STRAIN_NOLINES
Orange: Range from GDS-CALIB_STRAIN_CLEAN
started scan of OMC alignment started with no squeezing: April 26th 2024 16:36:47 ended at 17:30 UTC
I used this jupyter notebook from Gabriele updated with the scan times below and found at: /ligo/home/jennifer.wright/Documents/OMC_ALignment/OMC_Alignment_2024_04_26_2.ipynb
start 1398184622 GPS
end 1398187822 GPS
The new offsets are found relative to the old offsets by tuning the red lines in this plot to match the peak of the 410 - 411 Hz band-limited RMS (BLRMS) of the OMC DCPDs against the changing OMC ASC loop offsets. This works because the 410 Hz calibration line height scales with optical gain on the OMC DCPDs.
If one looks at the GDS-CALIB-STRAIN BLRMS at 800-900 Hz this dependence cannot be seen (the current value is favoured in these plots) and since these BLRMS are related to shot noise this could mean the squeezer is not well-matched to the OMC currently as suggested by Gabriele here.