FAMIS Link: 26010
Only CPS channels which look higher at high frequencies (see attached) would be:
TITLE: 09/24 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 4mph Gusts, 2mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.20 μm/s
QUICK SUMMARY:
15:01 UTC I flipped the polarity the MC servo board via H1:IMC-REFL_SERVO_IN1POL to break the lock after the inlock charge measurements were finished.
TITLE: 09/24 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY: H1 remained locked the whole shift with one candidate event. Took some time to try and improve SQZ alignment, although it didn't seem to initially help improve range.
H1 has been locked for almost 7 hours.
I took H1 out of observing from 01:58 to 02:08 UTC (3:50 into lock stretch, soon after L1 lost lock) to touch up SQZ alignment since high frequency noise didn't look great. I used the SCAN_ALIGNMENT_FDS and SCAN_SQZANG_FDS states in the SQZ_MANAGER Guardian to do this, and it looks like high frequency noise has improved, but I can't say the same for range (see attached trend of DARM BLRMS above 500Hz and range).
It seems that running these SQZ alignment optimization states somehow made range worse?
EDIT: attaching SQZ BLRMS comparison before/after alignment
TITLE: 09/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: Commissioning tasks completed: A2Ls gains, HAM1 PEM shaking tests, phasing POP9. We've been locked for a little over an hour, conditions are calm.
LOG:
| Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
|---|---|---|---|---|---|---|
| 23:58 | SAF | H1 | LVEA | YES | LVEA is laser HAZARD | 18:24 |
| 14:30 | FAC | Karen | Optics lab, vac prep | N | Tech clean | 14:51 |
| 15:44 | PEM | Robert | LVEA | Y | Turn on HAM1 shaker | 15:48 |
| 16:00 | FAC | Karen | MidY | N | Tech clean | 17:04 |
| 16:30 | FAC | Kim | MidX | N | Tech clean | 17:17 |
| 16:45 | VAC | Janos | MidY | N | VAC checks, mech room | 17:26 |
| 16:47 | CAL | Tony | PCAL lab | Y | PCAL work, tues prep | 17:39 |
| 17:10 | PSL | Sheila | LVEA | N | Plug in cable at PSL racks | 17:15 |
| 18:32 | PEM | Robert | LVEA | Y | Turn off HAM1 shaker | 18:38 |
| 18:33 | PSL | Sheila | LVEA | Y | Unplug cable at PSL racks | 18:38 |
| 19:02 | CAL | Tony | PCAL lab | Y | PCAL work | 19:17 |
| 20:29 | CAL | Tony | PCAL lab | Y | PCAL work | 21:49 |
| 22:03 | CAL | Tony | PCAL lab | Y | PCAL work | 22:48 |
TITLE: 09/23 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 13mph Gusts, 8mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.14 μm/s
QUICK SUMMARY: H1 has been locked for about an hour.
This morning we changed the demod phase of the POP 9 sensor. The overall summary is that this has a very similar impact to adding a PRCL offset, reducing the PRCL to REFL RIN coupling, and slightly increaing power in the PRC, but not changing the coupling of PRCL noise to DARM. I've turned off the offset, added a new phasing, and updated the PRCL to SRCL subtraction in the LSC input matrix.
More details:
I used a 702.1 Hz frequency noise injection, (template found in userapps/lsc/h1/templates/phase_LSC_sensors_frequency_exc.xml) and adjusted the POP9 phase to reduce the appearance of the frequency injection in Q (screenshot shows initial to final settings change in Q peak). I used Elenna's template to make a PRCL injection and measure the coupling to RELF RIN and DARM during this move, see screenshot. Adjusting the phase reduced the PRCL to REFL RIN coupling in a way that's similar to what Elenna has seen by adjusting the PRCL offset (see 79989 for example). Also similar to what Elenna has seen with the PRCL offset, this has very little impact on the PRCL to DARM coupling. The ndscope screenshot shows how this impacted REFL and POP powers, you can compare the time when I turned off the offset to the time when I tried reverting the phase to the original setting after finding the new setting, the two things have a simlar impact on the reflected power and the power in the PRC.
One interesting observation is that the phase that minimized the PRCL to REFL RIN coupling (as shown by the sign flip in the transfer function), is different from the phase that minimzed the frequency injection coupling to POP 9Q, by 2 degrees. I've left this at the phase that minimizes REFL RIN coupling. The impact on the power build ups is small enough that this two degree difference can't be evaluated using them.
Another observation is that the change in phasing doesn't seem to have an impact on the PRCL spectrum, spectrum screenshot.
Lastly, I did another PRCL excitation to measure the coupling to POP 45 and POP9 I, using the template in userapps/lsc/h1/templates/SRCL/SRCL/SRCL_input_matrix_git_rid_of_PRCL.xml (excuse the typo). I used this measurment to try to zero the PRCL coupling to SRCL ((POP45/PRCL)*MTRX_5_3 + (POP9I/PRCL)*MTRX_5_1 = 0, and found that this matrix element needed to be updated from 0.1185 to 0.1408. This was last updated by Jenne Driggers in 70919. The update reduced the SRCL to PRCL coupling by about 20dB, shown here.
Lastly we edited the guardian to not use the PRCL offset, and update the PRCL to SRCL input matrix element, and accepted the new matrix and phasing in SDF (in the observe file, and now also in the safe file).
Craig killed the lock by changing the POP A 9 phasing rotation by 5 degrees in one go.
Do not do this, instead use some cds step or script to change the rotation by a small amount over some time.
Lockloss at 21:17 UTC
FAMIS 31052
No major events of note this week. PMC reflected power seems to be holding mostly steady now, like we started to see last week.
Related detchar request: #172
Key points
11.9 Hz comb is present in some ASC, IMC and ISI-HAM5 channels:
Fscan data on 2024-04-08 was analyzed with a 2-week duration. 11.9 Hz comb is common at both observatories. The 1st and 3rd harmonics (11.9hz and 35.7hz) are the strongest peaks to study.
Details
*The method is adapted from #77990.
The stamp-pem-comparison tool was used first to pick out possible witnesses from low-resolution STAMP-PEM data. The result of 2024-06 -- 2024-08 is shown in Figure 1. I then followed up the analysis with week-long Fscan data on 2024-04-08. This date was chosen because the comb appeared strong then, according to alog 72866. Figures 2-7 are the coherence plots for the witness channels listed above. The interactive plots for some more auxiliary channels, plots of data from June, speclong data and data spanning 2 weeks can be found under https://ldas-jobs.ligo-wa.caltech.edu/~zhiyu.zhang/11.9Hz_appearance/. These other plots confirm the same channels. The comb is not visible in one day in these auxiliary channels.
The results of this analysis only apply to LHO for now, but the same method can be applied to LLO data.
Sheila and I are still trying to determine if the a2l script can be helpful, or made helpful, and understand our coupling from these changes to DHARD and CHARD. We ran it today with both C&D HARD showing higher coherences with our current lock (attachment from Ryan C's alog80244). After running the script the largest change was to ITMY Y gain (-0.28 diff). This helped out DHARD from 15-35Hz, but made CHARD worse in 10-21Hz. We were then going to try and tune common by hand to see if we could make any difference, but we lost lock.
We decided to update the gains with the script results since this did help out our DHARD. Perhaps an acceptable trade off for now. Values for the Y gains have been updated in lscparams and SDF, but P was close enough that I left them alone.
We had the chance to try one ITM common step by hand before running out of time, but it seemed to help out CHARD in the lower frequencies that we care about and and not affect DHARD.
Final gains +0.1 ITMY=-2.43 ITMX=3.05
We are starting planned commissioning at 15:30 UTC. Some of the tasks to be worked on are:
Lockloss 15:45 UTC from a HEPI HAM1 trip
Back into Observing at 18:39 UTC, high freq SQZing doesn't look good now?
Mon Sep 23 08:11:39 2024 INFO: Fill completed in 11min 35secs
Jordan confirmed a good fill curbside.
TITLE: 09/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 3mph Gusts, 1mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.15 μm/s
QUICK SUMMARY:
Running the low range check, low freq PRCL, CHARD_Y (and at high freq), DHARD_Y coherence
TITLE: 09/23 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Two locklosses this shift, one from a PI ringup and another from an earthquake. Otherwise a quiet shift and lock acquisition has been straightforward.
