All models on h1seih45 glitched at 07:09:46 PDT (14:09:46 UTC). This appears to have broken the lock and caused guardian to start an initial alignment.
Symptoms are:
The models appeared to have resumed normal operation following the glitch, no restarts were needed. At the time of writing H1 is locked with a range of 160MPc.
TITLE: 10/31 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: USEISM
Wind: 5mph Gusts, 3mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.47 μm/s
QUICK SUMMARY:
Looks like we just finished an initial alignment and are starting to relock
H1 called for assistance at 13:13 UTC when SRM watchdogs tripped during the SRC alignment steps of initial alignment. After resetting the WDs, I just let Guardian try SRC align again, but SRM tripped during ACQUIRE_SRY. I reset the WDs again and took ALIGN_IFO to DOWN to manually align SRM a bit (didn't get too much improvement on the AS_A fringing, but some), and had Guardian try again. This time, there were no issues, and initial alignment finished without issue.
H1 is currently relocking and just got through DRMI.
TITLE: 10/31 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: Currently relocking, but we've had a few lock losses after DRMI and one at engage_asc_for_full_ifo. We've just made it past that point again.
Lockloss 0349
Averaging Mass Centering channels for 10 [sec] ...
2024-10-30 14:34:04.266740
There are 14 T240 proof masses out of range ( > 0.3 [V] )!
ETMX T240 2 DOF X/U = -0.755 [V]
ETMX T240 2 DOF Y/V = -0.707 [V]
ETMX T240 2 DOF Z/W = -0.473 [V]
ITMX T240 1 DOF X/U = -1.549 [V]
ITMX T240 1 DOF Y/V = 0.328 [V]
ITMX T240 1 DOF Z/W = 0.452 [V]
ITMX T240 3 DOF X/U = -1.611 [V]
ITMY T240 3 DOF X/U = -0.797 [V]
ITMY T240 3 DOF Z/W = -1.997 [V]
BS T240 1 DOF Y/V = -0.404 [V]
BS T240 3 DOF Y/V = -0.317 [V]
BS T240 3 DOF Z/W = -0.502 [V]
HAM8 1 DOF Y/V = -0.436 [V]
HAM8 1 DOF Z/W = -0.758 [V]
All other proof masses are within range ( < 0.3 [V] ):
ETMX T240 1 DOF X/U = -0.04 [V]
ETMX T240 1 DOF Y/V = -0.066 [V]
ETMX T240 1 DOF Z/W = -0.098 [V]
ETMX T240 3 DOF X/U = -0.055 [V]
ETMX T240 3 DOF Y/V = -0.111 [V]
ETMX T240 3 DOF Z/W = -0.058 [V]
ETMY T240 1 DOF X/U = 0.015 [V]
ETMY T240 1 DOF Y/V = 0.136 [V]
ETMY T240 1 DOF Z/W = 0.192 [V]
ETMY T240 2 DOF X/U = -0.069 [V]
ETMY T240 2 DOF Y/V = 0.187 [V]
ETMY T240 2 DOF Z/W = 0.029 [V]
ETMY T240 3 DOF X/U = 0.206 [V]
ETMY T240 3 DOF Y/V = 0.04 [V]
ETMY T240 3 DOF Z/W = 0.128 [V]
ITMX T240 2 DOF X/U = 0.129 [V]
ITMX T240 2 DOF Y/V = 0.265 [V]
ITMX T240 2 DOF Z/W = 0.229 [V]
ITMX T240 3 DOF Y/V = 0.124 [V]
ITMX T240 3 DOF Z/W = 0.102 [V]
ITMY T240 1 DOF X/U = 0.083 [V]
ITMY T240 1 DOF Y/V = 0.084 [V]
ITMY T240 1 DOF Z/W = -0.063 [V]
ITMY T240 2 DOF X/U = 0.05 [V]
ITMY T240 2 DOF Y/V = 0.182 [V]
ITMY T240 2 DOF Z/W = 0.1 [V]
ITMY T240 3 DOF Y/V = 0.072 [V]
BS T240 1 DOF X/U = -0.174 [V]
BS T240 1 DOF Z/W = 0.082 [V]
BS T240 2 DOF X/U = -0.099 [V]
BS T240 2 DOF Y/V = 0.002 [V]
BS T240 2 DOF Z/W = -0.126 [V]
BS T240 3 DOF X/U = -0.213 [V]
HAM8 1 DOF X/U = -0.286 [V]
IMC tag on this one, ending a 1 hr 48min lock.
Following instructions from alog76751 and from Sheila herself, I ran the CARM olg python script located in /ligo/gitcommon/psl_measurements/. Sheila had already hooked up the SR785 at the PSL racks earlier in the day while we were relocking, so it was easy enough for me to check that we could connect to it through GPIB (checked with ipython like Craig did in alog64204), then run the commands listed in alog76751. After I ran it, I then went out into the LVEA and unplugged and turned off the SR785, as well as the LVEA lights.
Since this plot is saved as a pdf, its hard to say exactly what the UGF is, but it looks around 17kHz just as it has been, consistent with 76751 & 76448 but a little higher than 70920 and 65676 and 67584.
TITLE: 10/31 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Earthquake
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: USEISM
Wind: 14mph Gusts, 9mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.49 μm/s
QUICK SUMMARY: After the earthquake we started an initial alignment, in which Oli only had to adjust IM4. Now while locking PRMI, the POP90 signal isn't as high has before the earthquake when locked. Trending the PRs, PR2 is a little bit off in Y from before, so I've tried to keep PRC1 on and move PR2 slowly toward its old position while PRM followed. I'm not too sure this is helping at all though. Once this is done I'll try more DRMI.
TITLE: 10/30 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Earthquake
INCOMING OPERATOR: TJ
SHIFT SUMMARY: Trying to relock after the huge earthquake off the coast of Oregon knocked us down. Currently at PRMI_ASC and TJ is trying to touch up PRMI.
LOG:
14:30 In tail end of an initial alignment
14:33 Initial alignment done, relocking
15:26 NOMINAL_LOW_NOISE
15:26 Observing
15:49 Out of Observing to adjust CARM gain
- Trying to recreate FSS glitches
15:50 Back into Observing
16:09 Lockloss
16:10 Initial alignment
- SRC wouldn't lock and SRM tripped twice
16:37 Took us to DOWN and just started relocking
- Lockloss from LOCKING_ARMS_GREEN
- Lockloss from ACQUIRE_DRMI_1F
- IMC took 15 minutes to relock. Relocked after I took it to OFFLINE for a few minutes
17:55 NOMINAL_LOW_NOISE
17:58 Observing
18:00 Out of Observing for PSL makeup air check
18:32 Back to Observing
20:17 Lockloss due to earthquake
Tripped:
- ISI HAM{2,3,4,5,7,8}, BS, {E,I}TM{X,Y}
- SUS PR2, PR3, SR2, SRM, IM4, OFI, TMSY
21:45 Starting initial alignment
- Could not get XARM IR due to the IMs having drifted during the earthquake. I trended them back with driftmon and adjusted sliders until they were back to where they were before the earthquake.
22:36 Initial alignment finished, relocking
- Lockloss from PRMI_ASC x2
- Lockloss from LOCKING_ARMS_GREEN
- Lockloss from FIND_IR
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
14:57 | FAC | Karen | OptLab, VacPrep | n | Tech clean | 15:25 |
16:52 | VAC | Janos | Mid/Ends | n | Checking receiving areas | 17:18 |
17:06 | FAC | Tyler, contractor | Mids | n | In chiller yards, mech rooms | 19:39 |
18:01 | PEM | Robert | LVEA | n | Checking PSL makeup air | 18:32 |
18:01 | PSL | Jenne | LVEA | n | Spectrum of FSS output | 18:32 |
18:29 | FAC | Kim | H2 | n | Tech clean | 18:43 |
Reran all O4b locklosses on the locklost tool with the most up to date code, which includes the "IMC" tag.
I used the lockloss tool data since the emergency OFI vent (back online ~23rd August) until today and did some excel wizardry (attached) to make the two attached plots, showing the number of locklosses per day tagged with IMC and without tag IMC. I made this plots for just locklosses from Observing and all NLN locklosses (can include commissioning/maintenance times), including:
Attaching plots from zooming in on a few locklosses:
Time | Tags | Zoom Plot | Wide Plot |
2024-10-31 12:12:26.993164 UTC (IMC) | OBSERVE IMC REFINED | annotated plot | plot |
2024-10-30 12:16:33.504883 UTC (IMC) | OBSERVE IMC REFINED | annotated plot | plot |
2024-10-30 16:09:21.548828 UTC (Normal) | OBSERVE REFINED OMC_DCPD | N/A | annotated plot |
The 10-31 zoom plot notes the framerates of the channels: ASC, REFL and NPRO_PWR are 2kHz and GS13 is 4kHz, the others are 16kHz.
Since September 18th we've had 21 locklosses from NLN tagged as FSS_OSCILLATION, of these 20 also had the IMC tag. Since September 12th, we've had 49 locklosses from NLN tagged IMC, so roughly 40% of these IMC locklosses have the FSS oscillation tag, since the NPRO was swapped we don't have any tagged with FSS_OSCILLATION.
(Reminder, the FSS_OSCILLATION tag is an old tag, intended for a different problem, but it tags times where the FSS fast mon goes above a treshold.)
Updated plot attached of NLN locklosses tagged with and without the IMC tag.
J. Freed
I followed Step 1 of the double mixer test plan in T2400327 under "1. Characterize frequency references."
PNSPIDACTestStand.pdf Shows the results in dBc/Hz. And PNSPIDACTestStandrad.pdf shows the result in rad/sqrt(Hz).
Besides the 80MHz standard reference there were 2 devices under test, the IFR 2023A and the SRS SG382. These two devices went under 3 tests involving different combinations of
1. Timing to a 10MHz frequency standard produced by the 80MHz Standard. (Time Standard)
2. PLL locking to a different 80MHz frequency ref through the tune in port. (Lock)
During this process it was assumed that the 80MHz standard and the added 80MHz ref would have a simmilar noise profile as they come from a simmialar OCXO.
A 4th test was added to the Time Standard/No Lock test which used the SR785s internal high pass filter (-3dB at 0.16Hz) to remove some of the DC components from the test. This is because the results of the initial test were inconclusive as the noise floor of the SR785 was too high. The noise floor was too high because there was a DC signal that caused the input range of the SR785 to be about 20dB. The high pass filter, removed the DC signal, lowering the noise floor at the cost of signals below about 0.2Hz not being accurate. We believe this is caused by the fact that while the PLL locking can be controled (tries to lock signals to destructivly interfere so to lower output power for Phase noise tests), there was no control by the Time Standard on phase differences between oscilators. As Time Standard/ No lock, showed the best results above 0.06Hz and is closest to the SPI set up design, this fact may be important when doing futher tests.
Between IFR and SRS, the SRS showed better phase noise performance below 7kHz. While IFR showed better performance above 7kHz. As such, SRS shows more promise in SPIs phase noise range of interest 0-4096Hz.
After a talk with Jeff what is really important to show is the TIme Standard/Lock which is the 80 MHz OCXO, IFR and SRS which we believe is most represntative of phase noise
These are, one at a time, locked to another 80 MHz REF OCXO. In this it was assumed that the 80 MHz OCXO and the 80 MHz REF OCXO would produce the same phase noise, as such contribute equally to the output phase noise. As such the output was manually halved to represent the only the 80 MHz OCXO. As stated before these measurments also had a Time Standard (sometimes called time sync) where the 80 MHz OCXO is synced to the site's 1PPS. And the IFR and SRS have a 10MHz signal time standard signal that was produced by the 80 MHz OCXO divided by 8 and sent into the back of the devices.
PNSPIDACTestStandrad(sync_lockOnly).pdf Shows only the results of the Time Standard/Lock, which we believe to be the most represntative of the phasenoise of these devices.
Since it was assumed that the two OCXOs would have the same phase noise, this also makes our noise limit equal the OCXO. As such, it can be seen from this graph that we are at the noise limit in measuring the phase noise of the IFR and SRS between 0.1Hz-10Hz.
Lockloss @ 10/30 20:17UTC due to 4.8 earthquake in Oregon. We lost lock very soon after I noticed it coming in on Picket fence. We had been Locked for 2 hours 22 mins
There was a 6.1 from off the coast of OR (cascadian fault area), then a minute later a 4.3 from central OR. Every ISI except for HAM6 tripped
Our frequency noise and contrast defect (measured at the OMC) are lower than they ever have been in O4 (contrast defect, frequency noise). As a part of trying to track down what may have caused this reduction, I tracked the coherence of DARM with the LSC REFL A RIN, using that as a witness to frequency noise, as it was used in OAF for online frequency noise cleaning in O4a (source: 72276 and poking around the OAF screens).
I tried to pick times that were a few hours into the lock to avoid thermalization confusion. I also used only observing data.
There are a couple ideas about what could have caused this improvement. A short list:
These are the times I used. All of these times were at the same 60 W input power from the PSL:
Dec 10 2023: O4a time, no WFS offset in use, EY ring heater set to 1 W (1386244818)
Apr 11 2024: O4b time, before the OFI problems, WFS offset in use, EY ring heater set to 1 W (1396950886)
Jul 10 2024: O4b time, just before OFI repair vent, WFS offset in use, EY ring heater set to 1 W (1404656647)
Sept 14 2024: O4b, after OFI repair, WFS offset in use, EY ring heater set to 1 W (1410432000)
Sept 20 2024: O4b, after OFI repair, WFS offset set OFF, EY ring heater set to 1 W (1410855190)
Oct 22 2024: O4b, after OFI repair, WFS offset set OFF, EY ring heater set to 1.1 W (1413635762)
Here are some notes for the comparison of these times:
All of these O4 times show less coherence than the O4a time. Based on this data, it seems like the WFS offset did have an impact on the frequency noise. It also seems like the various vents with output port changes could affect the frequency noise, but the overall beam alignment in the arms could have changed during the vent. For example, we did adjust the camera offsets/ADS gains during the vent commissioning times. The change in frequency noise during the OFI problems (between April and July) could have a similar source, since we had to change a lot of alignment during that time. I'm not sure if any arm alignment was significantly changed though. Finally, it seems like this small ring heater change had no effect on the frequency noise.
Just a quick look at how the input jitter coherence has changed with these changes as well. For estimating input jitter, we generally use the IMC WFS A DC pitch and yaw channels, both for the noise budget and for jitter cleaning.
I used the exact same times as the freqeuency noise traces for ease, and I matched the colors too for easy comparison. Note: I used coherence with a channel that has no jitter subtraction to also avoid confusion.
This first plot compares the jitter coherence with DARM from all the times across the whole band in pitch and yaw. It's a bit hard to read. To make this easier, I'll break down the trace comparisons:
The most interesting point here (in my opinion) is that the improvement in frequency noise from the brown trace to the pink trace, that is, when we turned off the WFS offset, is opposite to the effect on the jitter noise. We've seen this before: improvements to frequency noise worsen jitter coupling and vice versa. I still don't understand that mechanism.
These are saved in the same template as the frequency noise plot: /ligo/home/elenna.capote/freq_noise_coherence_compare.xml
Daniel rightfully pointed out to me that REFL A RIN is a better measure of intensity noise than frequency noise. In the process of thinking about this, I realized that we found that PRCL had some offset present that increased DARM coherence to LSC REFL RIN. We first fixed this by applying a digital offset, and then Sheila rephased POP9 which had the same effect of reducing the coupling to REFL RIN and increasing power in the PRC. The digital offset was applied to PRCL from March 30 to May 6, and then again applied from Sept 16 until Sheila rephased POP 9 on Sept 23.
Since the PRCL offset/POP9 rephasing effects the coherence of DARM and REFL RIN, and to better ensure I am capturing frequency noise, I reran these measurements using coherence with the REFL SERVO CTRL channel.
Figure 1 We see similar improvement and worsening between O4a, Apr 12 O4b and Jun 10 O4b. Then, the three traces after the OFI vent show the same coherence, Figure 2. This indicates that the improvement between the brown (Sept 14) and pink (Sept 20) trace in the REFL RIN plot (original alog) is likely due to the changes in PRCL and not due to changes in frequency noise. In fact, the frequency noise coherence since the vent for these three times looks about the same.
This leads to the conclusion that the something about the OFI vent itself changed the frequency noise. We might be able to attribute it to an alignment change, but my sense is that whatever alignment change that occurred is small compared to the significant change in the output mode matching. I still don't full see how this then couples back to frequency noise, but it's worth some thinking and modeling.
Continuing on from Jenne's observation that there are still glitches in the new NPRO, I've tried to make a plot we can use to compare the glitch rate in the new and old NPROs, using the NPRO_PWR channel instead of the FSS channel which isn't available for the new NPRO.
I've used a 3 hour stretch of observing time for the old NPRO, and a three hour stretch before the time when Jenne made a plot in 80837. The ISS is not on for the new NPRO time, which is probably why the intensity is flcutuating and making it harder to see the small steps in power that are the glitches we are looking for. In the second panel, I've plotted the data high passed with a 0.05 Hz butterworth, this helps to show the glitches, although not perfectly (in either case). Based on this, the glitches look to be happening at a roughly similar rate, although somewhat less with the new NPRO.
This script in in sheila.dwyer/DutyCycle)4/dutycycleplots/PSL_glitches.py
Attaching another plot, showing that comparing our old NPRO to LLO during an observing stretch that started at midnight UTC time on Oct7th, LLO has no similar glitches.
Here's the same plot, but using a time from last night when the PSL environmental controls were off. There are still gltiches, but fewer.
These plot tiles show runs of Sheila's code looking for PSL power glitches on several days before / after the suspect date around Sept 12.
There's not a clear correlation between the glitches and locklosses. While maybe there's more glitches after Sept 12 (bottom row), the glitches don't consistently correlate with locklosses? Sept 14 is a good example of this: lots of glitches, the IFO stays locked through many of them.
2nd plot here shows overnight again with the swapped new laser. There are still glitches (though potentially less).
The PSL-PWR_NPRO_OUT_DQ channel seems to not be connected at LLO, which explains why the comparison plot a few comments above makes it look like L1 PSL is so much quieter than H1.
Adding screenshot of the NPRO power glitches over the past day. There are still glitches with the new laser -- not all glitches correspond to locklosses, but some do.
-Brice, Sheila, Camilla
We are looking to see if there are any aux channels that are affected by certain types of locklosses. Understanding if a threshold is reached in the last few seconds prior to a lockloss can help determine the type of lockloss, which channels are affected more than others, as well as
We have gathered a list of lockloss times (using https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi) with:
(issue: the plots for the first 3 lockloss types wouldn't upload to this aLog. Created a dcc for them: G2401806)
We wrote a python code to pull the data of various auxilliary channels 15 seconds before a lockloss. Graphs for each channel are created, a plot for each lockloss time are stacked on each of the graphs, and the graphs are saved to a png file. All the graphs have been shifted so that the time of lockloss is at t=0.
Histograms for each channel are created that compare the maximum displacement from zero for each lockloss time. There are also a stacked histogram based on 12 quiet microseism times (all taken from between 4.12.24 0900-0930 UTC). The histrograms are created using only the last second of data before lockloss, are normalized by dividing by the numbe rof lockloss times, and saved to a seperate pnd file from the plots.
These channels are provided via a list inside the python file and can be easily adjusted to fit a user's needs. We used the following channels:
After talking with Camilla and Sheila, I adjusted the histogram plots. I excluded the last 0.1 sec before lockloss from the analysis. This is due to (in the original post plots) the H1:ASC-AS_A_NSUM_OUT_DQ channel have most of the last second (blue) histogram at a value of 1.3x10^5. Indicating that the last second of data is capturing the lockloss causing a runawawy in the channels. I also combined the ground motion locklosses (EQ, Windy, and microseism) into one set of plots (45 locklosses) and left the only observe (and Refined) tagged locklosses as another set of plots (15 locklosses). Both groups of plots have 2 stacked histograms for each channel:
Take notice of the histogram for the H1:ASC-DC2_P_IN1_DQ channel for the ground motion locklosses. In the last second before lockloss (blue), we can see a bimodal distribution with the right groupling centered around 0.10. The numbers above the blue bars is the percentage of the counts in that bin: about 33.33% is in the grouping around 0.10. This is in contrast to the distribution for the observe, refined locklosses where the entire (blue) distribution is under 0.02. This could indicate a threshold could be placed on this channel for lockloss tagging. More analysis will be required before that (I am going to next look at times without locklosses for comparison).
I started looking at the DC2 channel and the REFL_B channel, to see if there is a threshold in REFL_B that can be put for a new lockloss tag. I plotted the last eight seconds before lockloss for the various lockloss times. This time I split up the times into different graphs based on if the DC2 max displacement from zero in the last second before lockloss was above 0.06 (based on the histogram in previous comment): Greater = the max displacement is greater than 0.06, Less = the max displacement is less than 0.06. However, I discovered that some of the locklosses that are above 0.06 for the DC2 channel, are failing the logic test in the code: getting considered as having a max displacement less than 0.06 and getting plotted on the lower plots. I wonder if this is also happening in the histograms, but this would only mean that we are underestimating the number of locklosses above the threshold. This could be suppressing possible bimodal distributions for other histograms as well. (Looking into debugging this)
I split the locklosses into 5groups of 8 and 1 group of 5 to make it easier to distinghuish between the lines in the plots.
Based on the plots, I think a threshold for H1:ASC-REFL_B_DC_PIT_OUT_DQ would be 0.06 in the last 3 seconds prior to lockloss
Fixed the logic issue for splitting the plots into pass/fail the threshold of 0.06 as seen in the plot.
The histograms were unaffected by the issue.
Added code to the gitLab
At the time of the glitch we had been relocking and at TRANSITION_FROM_ETMX. There seem to have been no issues at all from this - the initial alignment was automatically started after trying to relock took us into CHECK_MICH_FRINGES for the third time during the relock period, and went smoothly and without issue.
HAM4 and HAM5 GS13 signals following the glitch:
FRS32532
There are 8 Dolphin IPC channels which are sent by h1seih45 models (h1isiham4 and h1isiham5). They are all received by h1seiproc on h1oaf0. h1seiproc runs at 4kHz.
All 8 receive channels saw 4096 errors at the time of the glitch.
rcv model type snd host snd model ipc channel
h1seiproc PCIE h1seih45 h1isiham4 H1:ISI-HAM4_CPS_X_IPC_OUT
h1seiproc PCIE h1seih45 h1isiham4 H1:ISI-HAM4_CPS_Y_IPC_OUT
h1seiproc PCIE h1seih45 h1isiham4 H1:ISI-HAM4_SUSPOINT_SR2_L_OUT_IPC
h1seiproc PCIE h1seih45 h1isiham5 H1:ISI-HAM5_CPS_X_IPC_OUT
h1seiproc PCIE h1seih45 h1isiham5 H1:ISI-HAM5_CPS_Y_IPC_OUT
h1seiproc PCIE h1seih45 h1isiham5 H1:ISI-HAM5_SUSPOINT_OFI_L_OUT_IPC
h1seiproc PCIE h1seih45 h1isiham5 H1:ISI-HAM5_SUSPOINT_SR3_L_OUT_IPC
h1seiproc PCIE h1seih45 h1isiham5 H1:ISI-HAM5_SUSPOINT_SRM_L_OUT_IPC