ryan.short@LIGO.ORG - posted 20:28, Wednesday 22 May 2024 (77991)
Ops Eve Mid Shift Report
State of H1: Observing at 155Mpc
Quiet evening here so far; H1 has been locked and observing for 8 hours.
State of H1: Observing at 155Mpc
Quiet evening here so far; H1 has been locked and observing for 8 hours.
TITLE: 05/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: 3 locklosses today, relocking was straightforward, we've been locked for ~4 hours.
14:20 UTC lockloss, there was a ~13 Hz oscillation in SRCL, PRCL, and DARM
16:02 UTC back to Observing after some SQZer aligning
16:16 UTC lockloss, similar as earlier, ~13 Hz oscillation right before LL
Sheila removed a DARM filter alog77983
17:20 UTC back to Observing
18:37 UTC lockloss
The alignment seems to be degrading after each LL, DRMI/PRMI flashes are worse each time. I had to move PRM 15 microradians in pitch to help PRMI seeing AS AIR camera clearly pitched. On to DRMI AS AIR looks yawed now but the flashes are much better post ASC
Sheila measured the PR2 spot once we got close to NLN alog77988
22:19 I saw a DIAG_MAIN message "PMC PZT volts high" and shortly after the SQZer lost lock and dropped us out of Observing
I ran an alignment and angle scan to optimize squeezing after it relocked itself (SDF diffs) since we were already out of observing and I was just thinking that SQZing wasn't looking great at high frequency, the trace on nuc33 didn't look much different after finishing and DARMs noise still looks elevated at high and low frequencies but the range seems to have increased by a few Mpcs.
22:32 UTC back to Observing
LOG:
| Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
|---|---|---|---|---|---|---|
| 15:18 | FAC | Karen | Optics & VPW | N | Tech clean | 15:48 |
| 18:05 | FAC | Karen | Woodshop/Firepump | N | Tech clean | 18:19 |
TITLE: 05/22 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 11mph Gusts, 8mph 5min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.18 μm/s
QUICK SUMMARY: H1 has been locked and observing for 3.5 hours.
Since we are considering reverting the PR2 spot move, I measured the spot positions by adjusting A2L gains for PR2, PRM, and PR3. The first attached screenshot shows the current sliders and pico position, the second screenshot shows the A2L gains in SDF.
| A2L gain | ||
| PRM Y2L | 0.48 | |
| PRM P2L | 1.76 | |
| PR2 Y2L | -0.39 | |
| PR2 P2L | -3.0 | |
| PR3 Y2L | 1.5 | |
| PR3 P2L | -0.3 |
Here is the calculation of what these a2l coefficients imply in spot position (fixing the typo of swapping the PR2 P2L and Y2L coeffs):
| A2L gain | Spot position [mm] | |
| PRM Y2L | 0.48 | 1.0 |
| PRM P2L | 1.76 | 3.6 |
| PR2 Y2L | -3.0 | -6.0 |
| PR2 P2L | -0.39 | -0.8 |
I don't have handy the conversion for the larger PR3 triple suspension's A2L coeff to spot position, and Sheila also mentioned that the error bars on that one are a bit larger, so I'm not quoting a spot position for PR3.
| PRM P2L | 1.7 | |
| PRM Y2L | 0.52 | |
| PR2 P2L | -0.38 | |
| PR2 Y2L | -7.5 | |
| PR3 P2L | -1.5 | |
| PR3 Y2L | 1.6 |
In the measurements above, I didn't mean that the PR3 gains had more uncertainty than the others, but that the pitch ones had more uncertainty than yaw, because when I was tuning pitch I sometimes didn't see a clear difference. PR3 yaw seemed similar to the other yaw measurements.
I've accepted this in the OBSERVE and the safe.snap. Also attached is a screenshot of the sliders at the time of this measurement.
https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1400438280
Back into Observing at 20:10 UTC after Sheila finished measuring the PR2 spot and clearing the SDF diffs, I reverted these for the test masses
We've had some difficulty with turning off the mad hatter boost (DARM1 FM2) in the new DARM state, 77640 and this is probably also the problem Tony was encountering in 77956.
This is a boost that was turned on in the DARM_OFFSET state and then turned off again in LOWNOISE_ESD_ETMX. Today I commented out the boost turning on, since it may not be necessary.
We locked in fairly windy conditions like this, with wind speeds up to 25mph.
The first attachment shows how H1's range has degraded over the last week, with the first incident of poor range happening before we started to move PR3.
It seems that there are mulitple issues. The squeezer seems to be intermittently adding low frequency noise, see 77969 and 77888. This morning I repeated the squeezer on / off test and see that the low frequency noise is worse than May 8th now but isn't from the squeezer. The low frequency noise could be explained by the PRCL coherence, which is higher than either SRCL or MICH coherence. (Similar to what Camilla saw last night 77976).
Looking at the trend of the range with PR3 alignment, it does seem that the nonstationarity is present when we have PR3 moved, and mostly gone when it is in the original position. There was one incident of low range right before the move, which seemed related to anthropogenic ground motion. The range dips at times when PR3 is moved do not seem related to the ground motion.
This morning I made an attempt to move the squeezer alignment to see if this would help with the low frequency noise. I put a length excitation on ZM5, and increased the amplitude until I saw fringe wrapping in DARM. This template is saved in useraps/sqz/h1/Templates/dtt/DARM_scatter_bad.xml I moved ZM5 - 47urad in yaw, and saw that this reduced the amplitude of the scatter shelf (screenshot). Once I ran the SCAN_ALIGNMENT script which adjusted ZM4+6 to reoptimize the squeezing, the shelf height was mostly back to it's original. I've left the squeezer in this new alignment, but I'm not sure it's worth pursuing this until a time when the intermittent squeezer problem is happening.
Wed May 22 10:08:52 2024 INFO: Fill completed in 8min 48secs
Gerardo confirmed a good fill curbside.
TITLE: 05/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 21mph Gusts, 17mph 5min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.14 μm/s
QUICK SUMMARY:
Back to NLN at 15:20UTC and back into Observing after some SQZer aligning at 16:02 UTC
Lockloss at 16:16 UTC just before 1 hour of lock time, HAM6 verbal callout before?
HAM6 ISI saturations during a lockloss are fairly common. Fast shutter launching can cause a handful of GS13 and actuator saturations, which is probably what the HAM6 verbal notification was for.
TITLE: 05/22 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Two locklosses with currently unknown causes this shift, otherwise relatively quiet. H1 is currently relocking up to START_TR_CARM.
LOG:
No log for this shift.
Lockloss @ 07:49 UTC - link to online lockloss tool
No obvious cause; much like last time, LSC-DARM saw the first motion.
FAMIS 20029
No major events of note this week; PMC REFL continues to rise as it has been.
I did some additional trending to look a bit closer at what else possibly lines up with the PMC REFL increase, but so far those have proved inconclusive, providing further evidence that there's some on-table alignment shift happening.
Lockloss @ 01:38 UTC - link to online lockloss tool
No obvious cause; LSC-DARM saw the first motion.
H1 back to observing at 03:00 UTC
We need to reduce the DHARD rms to make our SRCL to darm coupling more stationary, (77729 77666) I ran a noise injection to measure the DHARD P loop this morning.
Elenna measured the hard loops and compared them to a model while we had 430kW in the arms in 69597, today's measurement is with 375kW. I used a template I found in userapps/h1/asc/templates/DHARD/DHARD_P_broadband_excitation.xml, which I think is the one that Elenna tuned in 69597.
Attached is a very simple script that uses dttxml to get the transfer function data from an xml file, getting the IN2/exc/IN1/exc unbiased transfer function. I also plotted uncertainties based on 10506, calculating an uncertainty for magnitude and phase from in1/exc and in2/exc separately and adding them in quadrature (this is not the correct way to add these uncertainties).
It seems like we have room to add a boost to this loop.
For modeling purposes, here's a fit to the DHARD_P plant obtained from this measurement, after factoring out the current controller.
Z = [-0.37656602]
P = [-0.00292406 +0.j ,-0.11496697 +6.49363092j,
-0.11496697 -6.49363092j,-0.19955184+16.53674456j,
-0.19955184-16.53674456j]
K = 2176.925725327256
Here's a possible design for a boost to improve suppression in the region below 0.7 Hz
zpk([-2.723526385480632+i*3.098947495963098;-2.723526385480632-i*3.098947495963098],[-0.6734376457906343+i*2.23044514115136;-0.6734376457906343-i*2.23044514115136],0.9990715840784479)
I have saved this new boost as GVboost in DHARD P FM8, but I haven't yet loaded the filter file.
