filiberto.clara@LIGO.ORG - posted 11:15, Monday 03 June 2024 (78211)
LVEA Dust Monitors
Mon Jun 03 10:09:43 2024 INFO: Fill completed in 9min 39secs
Gerardo confirmed a good fill curbside.
We aren't able to get back up right now due to high winds that are supposed to continue all day (currently >35mph but has already gone up to ~45mph). So we're going to be holding in DOWN until the wind calms down (windy.com says 3:00 UTC but we'll hope for earlier).
We're taking this as an opportunity to do some tasks that require the ifo to be down that would otherwise be done during tomorrow's maintainance.
FAMIS 20031
The main event from this past week was our incursion to investigate PMC losses (alog78093). PMC REFL is still high, but after our work it seems there was a jump up of about 1.3W. We believe this is due to some alignment shift into the PMC (likely from drag wiping M11 and having the environmental controls on for a couple of hours) evidenced by the change in the PMC REFL spot on the camera. Tomorrow during maintenance I plan on tweaking the alignment with the picos to hopefully bring it back to a more reasonable level.
Interestingly, there also appears to have been a change in the outputs of the NPRO and the diodes in both amplifiers at the time of our work in the enclosure. While the overall power output of the NPRO and amps are largely unchanged, I find this interesting as nothing was done with any of these components (shutters, pump current, etc.) except for the power watchdogs being turned off temporarily. Perhaps this behavior is simply a result of the environmentals being slightly different while working in the enclosure.
Monthly FAMIS Check (#26490)
Note: This is my first time I have run the scripts for these in O4. So I opened up the scripts to make sure there were no excitations to bump H1 out of Observing. Probably complete coincidence, but when I opened the T240 script via gedit, H1 had a lockloss! (I had Verbal running at the time on NoMachine session.) I'm sure it wasn't me, but just making a note. :)
T240 Centering Script Output:
Averaging Mass Centering channels for 10 [sec] ...
2024-06-03 08:44:03.268450
There are 15 T240 proof masses out of range ( > 0.3 [V] )!
ETMX T240 2 DOF X/U = -0.461 [V]
ETMX T240 2 DOF Y/V = -0.33 [V]
ETMX T240 2 DOF Z/W = -0.395 [V]
ITMX T240 1 DOF X/U = -1.271 [V]
ITMX T240 1 DOF Y/V = 0.346 [V]
ITMX T240 1 DOF Z/W = 0.453 [V]
ITMX T240 3 DOF X/U = -1.315 [V]
ITMY T240 3 DOF X/U = -0.597 [V]
ITMY T240 3 DOF Z/W = -1.671 [V]
BS T240 1 DOF Y/V = -0.363 [V]
BS T240 3 DOF Y/V = -0.311 [V]
BS T240 3 DOF Z/W = -0.454 [V]
HAM8 1 DOF X/U = -0.332 [V]
HAM8 1 DOF Y/V = -0.427 [V]
HAM8 1 DOF Z/W = -0.706 [V]
All other proof masses are within range ( < 0.3 [V] ):
ETMX T240 1 DOF X/U = -0.113 [V]
ETMX T240 1 DOF Y/V = -0.078 [V]
ETMX T240 1 DOF Z/W = -0.123 [V]
ETMX T240 3 DOF X/U = -0.067 [V]
ETMX T240 3 DOF Y/V = -0.202 [V]
ETMX T240 3 DOF Z/W = -0.065 [V]
ETMY T240 1 DOF X/U = 0.062 [V]
ETMY T240 1 DOF Y/V = 0.094 [V]
ETMY T240 1 DOF Z/W = 0.164 [V]
ETMY T240 2 DOF X/U = -0.09 [V]
ETMY T240 2 DOF Y/V = 0.165 [V]
ETMY T240 2 DOF Z/W = 0.08 [V]
ETMY T240 3 DOF X/U = 0.178 [V]
ETMY T240 3 DOF Y/V = 0.087 [V]
ETMY T240 3 DOF Z/W = 0.101 [V]
ITMX T240 2 DOF X/U = 0.151 [V]
ITMX T240 2 DOF Y/V = 0.256 [V]
ITMX T240 2 DOF Z/W = 0.248 [V]
ITMX T240 3 DOF Y/V = 0.149 [V]
ITMX T240 3 DOF Z/W = 0.136 [V]
ITMY T240 1 DOF X/U = 0.084 [V]
ITMY T240 1 DOF Y/V = 0.1 [V]
ITMY T240 1 DOF Z/W = 0.005 [V]
ITMY T240 2 DOF X/U = 0.07 [V]
ITMY T240 2 DOF Y/V = 0.237 [V]
ITMY T240 2 DOF Z/W = 0.091 [V]
ITMY T240 3 DOF Y/V = 0.063 [V]
BS T240 1 DOF X/U = -0.165 [V]
BS T240 1 DOF Z/W = 0.132 [V]
BS T240 2 DOF X/U = -0.067 [V]
BS T240 2 DOF Y/V = 0.05 [V]
BS T240 2 DOF Z/W = -0.113 [V]
BS T240 3 DOF X/U = -0.156 [V]
Assessment complete.
STS Centering Script Output:
Averaging Mass Centering channels for 10 [sec] ...
2024-06-03 09:03:13.267069
There are 2 STS proof masses out of range ( > 2.0 [V] )!
STS EY DOF X/U = -4.047 [V]
STS EY DOF Z/W = 2.792 [V]
All other proof masses are within range ( < 2.0 [V] ):
STS A DOF X/U = -0.496 [V]
STS A DOF Y/V = -0.709 [V]
STS A DOF Z/W = -0.681 [V]
STS B DOF X/U = 0.376 [V]
STS B DOF Y/V = 0.958 [V]
STS B DOF Z/W = -0.456 [V]
STS C DOF X/U = -0.655 [V]
STS C DOF Y/V = 0.886 [V]
STS C DOF Z/W = 0.356 [V]
STS EX DOF X/U = -0.06 [V]
STS EX DOF Y/V = 0.011 [V]
STS EX DOF Z/W = 0.051 [V]
STS EY DOF Y/V = 0.048 [V]
STS FC DOF X/U = 0.244 [V]
STS FC DOF Y/V = -1.03 [V]
STS FC DOF Z/W = 0.667 [V]
Assessment complete.
Lockloss @ 06/03 15:29 UTC, probably due to wind or a small local earthquake (or both)
16:35 UTC We're going to be holding in DOWN until the wind calms down (windy.com says 3:00 UTC but we'll hope for earlier)
We're taking this opportunity to do some tasks that require the ifo to be down that would otherwise be done during tomorrow's maintanance.
TITLE: 06/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 16mph Gusts, 12mph 5min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.13 μm/s
QUICK SUMMARY:
Detector Observing and Locked for almost 6 hours. Highest winds are currently just above 20mph, but are supposed to get a lot higher today.
TITLE: 06/03 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Earthquake
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Wind and microseism have been increasing over the past few hours which is giving ALS some trouble on the relock. We're still relocking following the LL
Started locking with an IA, which ended up tripping SRM M3
01:02 UTC lockloss
02:03 back into Observing
07:17 lockloss from a 5.9 in the Atlantic
Lockloss from an earthquake, https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1401434227
https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1401411781
Back into Observing at 02:03
It looks like since this lock started, LSC MICH had been slowly getting louder (attachment1). Ground movement was low and wind was below 20 mph. On the test mass glitch/saturation side, the lockloss was seen by ETMX L3 first (attachment2).
Sheila, Camilla, Robert
A change in the ETMX measured charge over the O4a-O4b break (e.g. 78114 ) suggested that there might be a change in electronics ground fluctuation coupling. This is because the hypothesized mechanism for ground fluctuation coupling depends on the test mass being charged so that, as the potential of electronics (such as the ring heater and the ESD itself) near the test mass fluctuate with electronics ground potential, there is a fluctuating force on the test mass.
We swept the bias (see figure) and found that the minimum in coupling had changed from an ESD bias of about 150 V in August of 2023 ( 72118 ) to 58 V now, with the coupling difference between the two setting a factor of about ten (in other words, if we stuck with the old setting the coupling would be nearly ten times worse). Between January of 2023 and August of 2023, the minimum coupling changed from about 130 V to about 150 V, with the coupling difference between the two settings being less than a factor of two. The second page of the figure is from this August alog, showing the difference in the coupling between then and now. I checked the differences across the break for ETMY, ITMY and ITMX and the coupling differences across the break were not much more than a factor of two, so the change in ETMX, about a factor of ten, seems particularly large, as might be expected for a significant charge change.
I started to find the gain adjustment that we need to change the bias. To get to an offset of 70V, preserving the DARM UGF we need 436.41 in L3 drivealign L2L, an an offset of 2.0 in the BIAS filter.
TITLE: 06/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY: Currently working on trying to relock the ifo. We had SRM M3 trip again during initial alignment (happened two IA's ago on Friday), and we are at FIND_IR and are having issues finding COMM.
LOG:
14:30 Detector Observing and Locked for 15.5 hours
22:19 Lockloss from earthquake
- sitting in DOWN while the ground moves
22:30 Started an initial alignment
- We had SRM M3 trip again (it had tripped Friday afternoon during an initial alignment as well 78163)
23:09 In FIND_IR and can't get COMM beatnote up
Last week I investigated the stray beam hitting the bellows on the spool piece by HAM3. It turned out not to be reflected from the HAM3 viewport as I had first hypothesized, but was reflected by, or originating at PR3. Figure 1 shows that the shadow pattern indicates that the beam is coming from the HAM2 direction. Figure 2 shows that, at the viewport near where the beam hits, the viewport for the PRM camera, there is an excess of light coming from PR3, suggesting that the outer halo of the beam is visible from that viewport and the beam is coming from PR3. This beam may be slightly clipped by the MC baffle by HAM3 and worth more study.
TITLE: 06/02 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 11mph Gusts, 8mph 5min avg
Primary useism: 0.05 μm/s
Secondary useism: 0.10 μm/s
QUICK SUMMARY:
SRM M3 wd tripped during PREP_SRC_ALIGN
Back to Observing at 00:28 UTC
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
