Based on Oli's range checks (alog83063) we decided to run the a2l script and a PRCLFF measurement after getting run coordinator approval. Below are the results of the a2l script, a few moving quite a bit. These have been added into lscparams.py and they are not in SDF. Jenne will post the PRCLFF results.
RESULTS
Initial | Final | Diff | ||
ETMX | P | 3.34 | 3.23 | -0.11 |
Y | 4.9 | 4.91 | 0.01 | |
ETMY | P | 5.56 | 5.49 | -0.07 |
Y | 1.28 | 1.35 | 0.07 | |
ITMX | P | -0.66 | -0.53 | 0.13 |
Y | 2.97 | 3.21 | 0.24 | |
ITMY | P | -0.06 | 0.06 | 0.12 |
Y | -2.51 | -2.74 | -0.23 |
We reran the PRCLFF injection template to try and improve the range in the 20-50 Hz range. The template was at /opt/rtcds/userapps/release/lsc/h1/scripts/feedforward/PRCL_excitation_gain_adjust.xml.
The right two panels are the magnitude and phase of the PRCL to DARM transfer function.
We tried gains of 0.9 (starting value)
1.0
1.3
1.5
We found the TF was minimised in the 20-50Hz range using a gain of 1.3 in PRCLFF (pink trace).
The live trace was our last step (red) which was a gain of 1.5.
The coherences are shown in the bottom left corner (labels correct but colours don't correlate with the TF colours).
(NB: Ref 1 darm spectra in top left is old reference - ignore).
TJ added the value to lsc params and I accepted it in the OBSERVE snap file.
At the EY station the compressor is being replaced - after the one at EX is done. In this aLog, in the comments, the progress of this operation is tracked continuously, until the 1st startup by the supplier, Rogers Machinery. Another important consideration here, is that the purge line at EY needs to be replaced (based on an FTIR test - see DCC LIGO-E2300222-v2. As it can be seen, the level of contamination reaches even the 10 ug/cm2 value). This operation will be done after the April-May vent, so the EY station will be ready to be vented after O4. 02-25 (maintenance Tuesday): the old compressor was pulled out (it is temporarily stored in the EY receiving area). The beginning of the purge and TMDS lines with the associated brackets and unistruts were taken off. The new compressor unit and dryer skid were anchored in the mechanical room. Here it is important to mention that the orientation of the inlet was brought closer to the purge line inlet into the VEA, so the overall length of the associated circulation lines will be much shorter. Next is the electrical and pneumatic installation, which will be completed in the next 1-2 weeks.
The filter tree was installed and supports anchored to the slab. Ken also reports that electrical installation is complete. Connection to the purge air header is awaiting CF fittings from the supplier. However, startup testing can continue prior to header connection.
The 1st startup of the compressor was carried out by Rogers Machinery on March 18th, during maintenance hours.
Ran a low range check coherence check for a time during the early morning lock after we were thermalized (2025-02-26 10:05 UTC). Many of the channels came back clearly showing coupling between it and darm.
In almost all of them you can see that the coherence is higher in the last lock than the references, but the ones that stood out to me were:
Sheila, Matt, Camilla
We repeated the HD data set taken in 82202 as in 83022 we found we had pump depletion during these measurements so that the OPO trans powers were actually lower than reported. We had some issues at first which ended up being that with HAM7 ISI tripped the optics were moving around too much, plot of optics here. After we fixed that, we retook the data, so that our real data set is in 83039. Below documents the steps taken and initial data that we ended up not trusting.
Then started data taking:
Sheila and Matt measured the LO OLG as 2.5kHz 80deg phase margin is LO loop with gain -12 LO on LOCKED_HD with opo_grTrans_setpoint_uW = 80uW before we started.
One we got to the 110uW measurements, we felt the squeezing was unstable, moving independently of the SQZ angle, steps taken to help this:
Data saved to camilla.compton/Documents/sqz/templates/dtt/20250225_HD.xml
FC2 is misaligned during this dataset.
Type | NLG | SQZ dB @ 1kHz | Angle | DTT Ref | Notes |
Dark Noise | N/A | N/A | ref 0 | This and shot noise was noisy <300Hz at times when the OPO was locking or scanning, unsure why. | |
Shot Noise | N/A | N/A | ref 10 |
Blocked SEED, LO only.
|
|
SQZ | 12 | -7.1 | 157 | ref1 |
opo_grTrans_setpoint_uW = 80uW
Amplified Max = 0.0107mW
Amplified Min = 0.00037mW
UnAmp = 0.00095
Dark = 6.5e-5
NLG = 11.9(max/min) and12.0 (usual method)
|
ASQZ | 12 | 14.7 | 243 | ref2 | |
Mean SQZ | 12 | 11.8 | N/A | ref3 | |
SQZ | 66 | -6.6 | 167 | ref4 |
opo_grTrans_setpoint_uW = 120uW
Amplified Max = 0.05347mW
Amplified Min = 0.0002933mW
UnAmp = 0.00095
Dark = 6.5e-5
NLG = 66 (max/min) and 60.3 (usual method)
|
ASQZ | 66 | 22.6 | 229 | ref5 | |
Mean SQZ | 66 | 19.7 | N/A | ref6 | |
SQZ | 23 | -7.0 | 156 | ref7 |
opo_grTrans_setpoint_uW = 100uW
Amplified Max = 0.0210425mW
Amplified Min = 0.00034922mW
NLG = 23.0 (max/min) and 23.7 (usual method)
|
ASQZ | 23 | 18.1 | 236 | ref8 | |
Mean SQZ | 23 | 15 | N/A | ref9 | |
SQZ | 36 | -7.2 | 165 | ref11 |
opo_grTrans_setpoint_uW = 110uW.
Amplified Max = 0.033029mW
Amplified Min = 0.00033752mW
NLG = 36.0 (max/min) and 37.2 (usual method)
OPO gain reduced -8 to -14. HAM7 WD untripped. Visibility again measured. |
ASQZ | 36 | 19.9 | 230 | ref12 | Rechecked after visibility adjusted, no change |
Mean SQZ | 36 | 16.9 | N/A | ref13 | |
SQZ | 36 | -7.2 | 165 | ref14 | Remeasured after visibility again measured. |
Wed Feb 26 10:16:27 2025 INFO: Fill completed in 16min 24secs
This is the second run of new rate-of-change code. I have created a new set of MEDMs and a new Plot format to show the rate-of-change channels and the new trip level.
MEDM:
The main medm shows the six rate-of-change channels as bar charts (TC-A = blue, TC-B = purple). The trip level (60degc) is shown as a grey bar, the first ROC channel to exceed this stops the fill.
The related trend MEDM has been extended to show the six ROC channels, keeping with the same color scheme.
PLOT:
The plot has an additional panel showing the six ROC channels. The trip level is shown as a horizontal line. Both panels show start/stop times as vertical lines.
TITLE: 02/26 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Aligning
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 7mph Gusts, 3mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.31 μm/s
QUICK SUMMARY:
Currently in PREP_FOR_LOCKING, looks like H1 MANAGER went into error at 15:29 UTC. I reloaded it and we've just started an initial alignment.
This is another instance of guardian issue #83. I think this is a race condition that we run into about two times a year, I need to find a way around it.
Summary
Initial call was because the IFO was waiting to turn on the OMC whitening since the violins are elevated, though I thought this was something we fixed. The whitening was safe to turn on minutes after I started looking at it, but the SQZer couldn't lock the FC. Once I fixed the FC alignment, I had to futz with the SQZ ASC, then all was well. There were some SDF diffs. Violin modes 5&6 of ITMY aren't damping well, not a new issue. Back to Observing at 0905UTC.
SQZ
H1:SQZ-FC_TRANS_C_OUTPUT wasn't getting flashes above 17 (the wiki says it should be above 100). I followed the instructions in the wiki and adjusted FC2 to get good flashes in the cavity and eventually got it to lock. It was left with a "FC ASC not on??" notification. Sure enough, H1:SQZ-FC_ASC_TRIGGER_INMON was at 1.5, still lower than the recently lower 2.0 trigger threshold(alog82853). I tried to touch up FC2 a bit more and got the trans output up to 112, but the trigger input was still at 1.5. I cycled SQZ_FC guardian node and was back in the same place. I then lowered the threshold to 1.5 and it turned on the ASC, temporarily raising the trans output and bringing the trigger input to 4.5. Range was at 146Mpc but we were still thermalizing so I didn't want to tune much else.
SDFs
There were two SDFs - H1:LSC-LOCKIN_1_OSC_TRAMP and H1:SYS-MOTION_C_PICO_I_CURRENT_ENABLE, both reverted.
Violins
While I was here I checked to make sure the violins were damping well. All seemed good except maybe ITMY 5&6. We've recently gone through some gain and phase changes to this mode (alog82977 alog82963). At this point mode 5 looked to be slowly decreasing, but mode 6 wasn't really moving. This was better than increasing though, so I left the settings as they were.
Violin mode ITMY mode 05/06 is damping fine using the nominal settings - FM6 + FM8 + FM10 Gain +0.01 (+30deg phase) during this (Wed morning) lock stretch.
TITLE: 02/26 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: TJ
SHIFT SUMMARY: The winds calmed down to the 20s and lower around 6 but locking issues persisted, the 2ndary microseism is still at or above the 90th percentile, so that wasn't helping us. There was a dolphin glitch but Dave helped me to get everything up and running. I just finished an IA as of the end of the shift.
LOG:
Ryan C, Dave:
At 20:14:41 Tue 25 Feb 2025 PST we had a corner station issue which put the IOP models for h1sush34 and h1lsc0 into a DACKILL state. First attachment shows the status before any resets had been issued, second shows overview and the iop models after DIAG_RESET and DAQ_CRC_RESET had been issued.
There were no dmesg messages on either h1sush34 and h1lsc0 from today. I checked that both of these front ends had their full complement of cards in their IO Chassis.
In prep for restarting the IOP models, which requires restarting all the models on these front ends, Ryan put HAM3,4 into a safe state. I engaged the SWWD bypass on the SEI system for HAM 3,4.
After restarting the models on h1sush34 and h1lsc0 they came back with no issues.
The initial cause of the crash is not clear. Timing of the IOP STATE_WORDs going offline suggests sush34 crashed first glitching lsc0 at that time, but lsc0 didn't go fully offline until 6 seconds later.
restart log
20:38:26 h1sush34 h1iopsush34
20:42:20 h1lsc0 h1ioplsc0
20:43:09 h1lsc0 h1lsc
20:43:33 h1lsc0 h1lscaux
20:43:51 h1lsc0 h1sqz
20:44:12 h1lsc0 h1ascsqzfc
20:44:40 h1sush34 h1susmc2
20:45:01 h1sush34 h1suspr2
20:45:20 h1sush34 h1sussr2
04:14 UTC HAM1 HEPI tripped and killed the lock, lots of red on CDS_OVERVIEW, something crashed. I called Dave who's gonna log on and help. Theres a DACKILL trip on iopsush34 and ioplsc0
I have recently reported that the “mystery” beam on the spool piece wall near HAM3 was coming from the direction of ITMX (82252). To further this investigation, I started photographing the area around the ITMs and BS as best I coluld through our viewports (there is not a good view towards HAM3). I found several unexpected distributions of light in the vertex:
1. 20 degree conical annular beams from ITMs
Both ITMX/CPX (Figure 1) and ITMY/CPY (Figure 3) cast an expanding annular “beam” towards the BS with a cone half angle of roughly 20 degrees from the main beam. My best guess is that it is produced by arm cavity light hitting the bevel of the ITMs (see cartoon in Figure 1). A good test of this would be to install the new test mass cage baffles at one or more of the ITMs at LLO (presuming Anamaria finds this beam at LLO) this upcoming break. The baffle should hide the bevel and eliminate the ring of light.
2. 45 degree conical annular beams from BS
The BS appears to cast an expanding annular “beam” with a cone half angle of 45 degrees, centered around the -X, -Y direction (Figure 2), and likely another annular beam, also with a half angle of 45 degrees, centered around the -X, +Y direction (evidence in Figure 3). I tried to find a geometry where the bevels were also the source of these beams but didn’t. My best guess is that the annular cone is produced by reflections of light from PR3 and the ITMs off of the inner surface of the circular cage around the BS, or the inside surface of the circular barrel of the BS itself (see drawings on third page of Figure 2).
3. Reflection of BS in ITM elliptical baffles likely visible at ITMY and HAM3
The BS beam spot is reflected towards ITMY by the slanted piece of the ITMX elliptical baffle (Figure 3). While the actual beam is not reflected towards ITMY (it isn’t clipped), the baffle reflects light towards ITMY that is scattered out of the main beam by only a few degrees.
Similar images were taken at LLO for comparison (see Alog 75626)
FLlamas - Tuesday, 2025-02-25
Start of report
Moved the Pcal upper beam at END-X to test for repeatability of the results seen on LHO:78373.
Recap:
As seen on first figure (chi_klm), the red squares highlight the inconsistency when moving the upper and the lower beam to the same direction (left aperture on target - fourth and fifth figures show the target) on the ETM. The other moves are consistent between upper and lower beam. Additionally, the second (2024_06_11_transition_upper_center2left_rawpcals_out) and third (2024_06_18_transition_upper_left2center_rawpcals_out) figure show the Pcal channels during the upper beam moving from the target center aperture to the left aperture and back. The blue color is for the PD values before making an actuation, the orange is for the values after the actuation, the title tells the actuation direction on the target and the x-axis is the time needed to average 10 hours within lock for each state (10 hrs before and 10 hrs after). From these plots we see that, during the upper-beam actuation to the left and back, the END-X Tx sensor - middle-left plot - decreased by 8 HOPs and 6 HOPs, affecting chi_XY. The END-X Rx value - top-left plot - dropping by 20 HOPs suggests additional losses of the beam downstream from the Tx sensor, potentially from clipping, but it is hard to see with the Tx changing simultaneously. There was an initial concern at the time of moving the upper beam that the actuations to the right aperture were the inconsistent ones, but after moving the lower beam we can have more confidence on the values corresponding to an actuation to the right aperture and raise concern on the actuations done to the left aperture.
Today:
Went to END-X to move the upper Pcal beam by actuating on yaw of the last folding mirror before the vacuum window (aka: the "inner beam" folding mirror.) The objective is to maximize the signal measured by the Rx PD when the target is in place. This is done by blocking the beam that will not be used and monitor the actuated beam with a voltmeter reading from "RX PD Mon" from the Pcal interface chassis (D1400153). The table below documents each relevant step from the procedure and the voltage used to assess such step.
Step | Comment | Keithley Voltage [V] |
---|---|---|
1 | Both beams | 3.387 ± 2e-3 |
2 | Block outer (lower) beam | 1.682 ± 1e-3 |
3 | Target on (fourth figure | 1.412 ± 5e-3 |
4 | After actuation (fifth figure | 1.570 ± 2e-3 |
5 | Target off | 1.683 ± 1e-3 |
6 | Unblock outer beam | 3.389 ± 2e-3 |
The increase in signal after the actuation could be from clipping on the center aperture. An extra step between 3 and 4 where the beam is "optimized" on the center aperture would reveal if there is such clipping. The previous alog from a Pcal upper-beam actuation to the left agrees that this location increases the Voltage signal from RX PD Mon but the data shows 20 Hops of clipping... odd.
Nominal plan is to get a few hours of lock to assess the results from this actuation, and return the beam to it's nominal "center" state on the following maintenance Tuesday.
End of report
original post: SEI 2513
I restored the MSO (Missoula, Montana) picket to the picket fence. Hopefully it will increase the reliability of the picket fence for the few earthquakes that come from the northeast.
Turns out they changed the sensor to a different data rate and it hadn't been mentioned in the data aggregator.
Please SVN up at the picket fence folder if you would like to get this change.
TITLE: 02/26 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Wind
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
SEI_ENV state: USEISM
Wind: 29mph Gusts, 17mph 3min avg
Primary useism: 0.12 μm/s
Secondary useism: 0.57 μm/s
QUICK SUMMARY:
03:49 UTC We reached OMC_WHITENING but the violins are a bit rung up, so we'll have to stay here and damp.
Sheila, Matt, Camilla
We aligned and took some SQZ HD data this morning but realized that the ZM optics were noisy with HAM7 tripped and the increased (60mph!! wind). After un-tripping HAM7, Matt and Sheila rechecked balancing and visibility, started at 98.3% but noisy, improved to 99.0%. Since then HAM7 tripped and was un-tripped again but assumed nothing would have changed.
NLG Measurements:
opo_grTrans_ setpoint_uW | Amplified Max | Amplified Min | UnAmp | Dark | NLG (usual) |
120 | 0.108354 | 0.000573291 | 0.0018491 | 6.6e-5 | 60 |
110 | 0.0656167 | 0.000599855 | 36.8 | ||
100 | 0.0413918 | 0.00062871 | 23.2 | ||
80 | 0.0209032 | 0.000681607 | 11.7 | ||
60 | 0.0121804 | 0.000745147 | 0.0018428 | 6.2e-5 | 6.8 |
40 | 0.00710217 | 0.000852173 | 3.98 |
Data saved to camilla.compton/Documents/sqz/templates/dtt/20250225_GOOD_HD.xml
FC2 is misaligned during this dataset.
Type | NLG | SQZ dB @ 1kHz | Angle | DTT Ref | Notes |
Dark Noise | N/A | N/A | ref 0 | This and shot noise was noisy <300Hz at times when the OPO was locking or scanning, unsure why. | |
Shot Noise | N/A | N/A | ref 10 |
Blocked SEED, LO only.
|
|
SQZ | 60 | -7.4 | 167 | ref1 | opo_grTrans_setpoint_uW = 120uW, OPO gain -14 |
ASQZ | 60 | 22.6 | 225 | ref2 | |
MSQZ | 60 | 19.6 | N/A | ref3 | |
SQZ | 37 | -7.3 | 164 | ref4 | opo_grTrans_setpoint_uW = 110uW |
ASQZ | 37 | 20.2 | 229 | ref5 | |
MSQZ | 37 | 17.2 | N/A | ref6 | |
SQZ | 23 | -7.4 | 161 | ref7 | opo_grTrans_setpoint_uW = 100uW |
ASQZ | 23 | 18.0 | 233 | ref8 | |
MSQZ | 23 | 15.0 | N/A | ref9 | |
SQZ | 12 | -7.3 | 151 | ref11 | opo_grTrans_setpoint_uW = 80uW, OPO gain -8 |
ASQZ | 12 | 14.5 | 246 | ref12 | |
MSQZ | 12 | 11.7 | N/A | ref13 | |
SQZ | 7 | -7.0 | 143 | ref14 | opo_grTrans_setpoint_uW = 60uW |
ASQZ | 7 | 11.7 | 253 | ref15 | |
MSQZ | 7 | 8.7 | N/A | ref16 | |
SQZ | 4 | -5.9 | 132 | ref17 | opo_grTrans_setpoint_uW = 40uW |
ASQZ | 4 | 8.9 | (-)85 | ref18 | |
MSQZ | 4 | 6.0 | N/A | ref19 |
I'm also attaching pictures of SR785 measurements of various loop gains.
Measurement | Time | Notes |
LO OLG | 11:28 | 2.5kHz UGF |
OPO OLG | 12:06 PST | -8dB gain OPO loop gain |
OPO OLG | 12:09 PST | -14 dB on OPO loop gain |
CLF OLG | 12:10 PST | 13.kHz UGF |
This data set is nicely fit by standard squeezing equations, and suggests we have 6% unexplained losses and very little phase noise.
In the attached PDF I took the median of the ASD from 500-700 Hz, subtracted dark noise in quadrature from each ASD, then calculated the dB relative to shot noise for squeezing, anti-squeezing and mean squeeze. I used the squeezing and anti-squeezing and opo transmission numbers to fit for the OPO threshold (in units of transmitted power), total efficiency of squeezing, and phase noise. The attached plot shows the resulting model plotted against the data, including mean squeezing and NLG measurements that were not used for fitting. The NLG plot does suggest that we are slightly underestimating our NLG with our measurements.
This suggests that the OPO threshold is at 156uW transmitted power, and that the totall efficiency is 83%. This can be compared to 73365 and to the expected losses from the loss tracking sheet and sqz wiki. Expected losses:
opo escape efficiency | 0.985 | |
3 SFI passes | (0.99)^3 = 0.97 | |
B:BS1 | 0.9897 | HAM7 total = 0.946 |
SQZT7 | 0.98 | |
visibilty | 0.99^2 | |
homodyne QE | 0.977 | |
total expected in homodyne | 0.887 |
With the measured efficiency of 0.833, this means we have 6% unexplained losses in HAM7 or SQZT7.