Ops EVE Shift End

TITLE: 03/28 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: None
SHIFT SUMMARY: We're Observing and have been Locked for over 12.5 hours now. Very quiet night!
LOG:

2300UTC Detector locked for 4.5 hours, commissioning wrapping up

2308 Into Observing

H1 ISI CPS Noise Spectra Check FAMIS

Closes FAMIS#25984, last checked in 76634

They all look very similar to at least the last few weeks of checks. The only thing that stood out to me was ITMY stage 2 V2 around 100Hz and 170Hz - the spikes there are slightly thicker than all the other stage 2 higher frequency spikes.

Ops Eve Midshift Status

We've now been Locked for over 9 hours and are Observing.

ZM alignment guardian

Vicky, Naoki, Nutsinee

To scan the ZM alignment, we copied the SCAN_ALIGNMENT state in SQZ_MANAGER guardian in LLO. After some debugging, we successfully ran this state. The result is saved in here.

https://lhocds.ligo-wa.caltech.edu/exports/SQZ/GRD/ZM_SCAN/

This state scans the ZM4/ZM6 COM and DIF P/Y. We need the proper diagonalization to define the COM and DIF, but we have not done it today. The state fits the BLRMS6 at 1.7kHz and finds the optimal ZM slider value for minimizing the BLRMS6 as shown in the first attachment. After each ZM scan, the SQZ angle is also scanned and the optimal SQZ angle is found as shown in the second attachment.

The third attachment shows the BLRMS. The T1 cursor shows when the sqz-optimized scan was done. After the scan, the BLRMS6 looked good, but the BLRMS3 (yellow) was not so good and the BNS range was below 150 Mpc. So we tweaked the sqz angle and the BNS range reached more than 150 Mpc.

The original SCAN_ALIGNMENT tries to find the minimum of squeezing, but we modified it so that it can also try to find the maximum of anti squeezing. The T2 cursor in the third attachment shows when the asqz-optimized scan was done. The result is saved here.

sqz-optimized: https://lhocds.ligo-wa.caltech.edu/exports/SQZ/GRD/ZM_SCAN/240327132206/

asqz-optimized: https://lhocds.ligo-wa.caltech.edu/exports/SQZ/GRD/ZM_SCAN/240327144407/

The fourth attachment shows the ZM slider after the sqz-optimized and asqz-optimized scan. The ZM4 Y is almost the same, but other ZM alignment is different by 10-20 counts between the sqz-optimized and asqz-optimized scan. The proper diagonalization of ZM4/6 would resolve it.

Since the SCAN_ALIGNMENT touches the TRAMP of ZM slider, we reverted it after the scan as shown in the fifth attachment.

Camera servo offset stepper tests set to run overnight

Jennie and I started the camera_servo_offset_stepper.py script to run for CAM2 (at 23:18UTC - 3:28UTC) should finish by 8:18pm and scheduled CAM1 for 8:30 to 12:30pm (3:30 to 7:30UTC). These didn't run yesterday 76732 as the IFO was unlocked. 

Ops Day Shift End

TITLE: 03/27 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing
INCOMING OPERATOR: Oli
SHIFT SUMMARY: We've been locked for over 4.5 hours and have just transitioned back to Observing for the rest of the evening. The one lock loss we had was possibly cuased by work on the floor. Relocking was straight forward, I ended up moving PRM to lock PRMI in an attempt to avoid an initial alignment. It took 57 min to relock.

• 1726 Lock loss. HAM1 HEPI tripped
• 1821Back to low noise
  • DRMI/PRMI looked awful when it first arrived. In an attempt to avoid an initial alignment, I let it run a Mich bright, then I moved PRM a fair amount in pitch and yaw to get PRMI to lock. DRMI locked up without issue after this. No other intervention was needed.
  • 57min from lock loss to NLN
• 2308 Observing

LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
16:09	VAC	Gerardo	site	n	Forklifting septum from woodshop to LSB receiving	16:39
16:09	ISC	Sheila, Artem	CR	n	ESD bias change	18:09
16:26	ISC	Daniel	LVEA	n	Look at PSL racks	16:45
16:46	FAC	Kim	H2	n	Tech clean	18:46
17:11	SQZ	Julian	OptLab	yes	SHG work	19:32
20:09	ISC	Sheila	LVEA	n	Checking on PSL racks	20:29
22:12	PEM	Robert	LVEA	n	Turn off amps, clean up	22:17
22:19	PEM	Robert	EX	n	Shaker meas	23:14

Ops Eve Shift Start

TITLE: 03/27 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 13mph Gusts, 11mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.27 μm/s
QUICK SUMMARY:

Detector has been Locked for 4.5 hours and commissioning is wrapping up.

Are we in danger of clipping on PR2?

Since we have been moving input alignment, seeing strange behavior, and have an increased PRCL coupling that we can't explain, I figured we should answer this question.

Short answer: probably not.

Longer answer and explanation:

Going back in time in the alog, I found several great references. First, this alog 31381 from Kiwamu that shows at one point the PR2 Y2L gain was -9.5, greater than our current value of -7.4, and the miscentering corresponded to 19 mm miscentered.

I also found these other references, 31402, 42601, and Koji's elog (thanks to the above alog and also Georgia). The beam miscentering can be calculated via d = 2* alpha * beta / D. Alpha is calculated by alpha = A2L * L_eul / (A2A * A_eul)

For an HSTS, d = 39.28 mm * alpha (Craig's comment in 42601)

PR2 Y2L = -7.4, L_eul = 0.25, Y2Y = 1 and A_eul = -5.23820 (for the UL coil).

Therefore, d = 39.28 mm * 0.37 = 14.53 mm

From Kiwamu in 31381, PR2 is 150 mm in diameter and the beam is about 6 mm. So this Y2L gain is fine, assuming that the coils are balanced.

A good test is probably to check that the PR2 coils are balanced.

CARM OLG

Daniel plugged in the SR785 into the common mode board this morning. 

I've followed the instructions in 64204, and 67214 summarized here:

make sure the excitation A is enabled on the common mode board, the 785 is plugged in.

cd /ligo/gitcommon/psl_measurements/templates
conda activate /ligo/home/craig.cahillane/.conda/envs/psl
python ../code/SRmeasure.py carm_olg_template.yml

The plot options in the template don't work.

to find your data go to: /ligo/gitcommon/psl_measurements/data/carm_olg and try ls -lrtp to find the most recent file 

To make a plot:

python ../code/quick_tf_plot.py /ligo/gitcommon/psl_measurements/data/carm_olg/CARM_OLG_27-03-2024_131841.txt

The CARM olg right now is something like 17 kHz, consistent with 76448  but a little higher than 70920 and 65676 and 67584.  These all look fine according to the loop stability, but we could try reducing the CARM gain a bit to be more similar to O4a.

I reduced the gain by 3dB on both inputs 1 and 2, resulting in the second attachment.  I've lowered the gain setting in laser noise supression to 3dB from 6dB as well so that we will run like this.

PcalX bump from 0-120 Hz

TJ, LouisD, TonyS, DriptaB, FranciscoL

There was an unexpected "bump" on PcalX at around GPS 1395546818. This was shortly after TJ attempted Detchar safety injections (76727).

Looked into H1:CAL-PCALX_TX_PD_OUT, RX_PD_OUT, OFS_PD_OUT, OFS_AOM_DRIVE_MON_OUT and OFS_ERR_OUT for any issues.

Observations:

• Bump travels across spectrum from 0 Hz to 120 Hz for an indefinite amount of time. The figures "PcalX_DTT_120.png", "...85.png", and "...40.png" illustrate the bump appearing at 120 Hz, 85 Hz, and 40-ish Hz, respectively.
• OFS_ERR_OUT sees the bump at what seemed to be a loop troubleshooting. The top plot on "PcalX_DTT_zoom_ERR.png" shows the bump appearing at ERR_OUT.
• Troubleshooting did not solve the issue. We did not see any bumps this morning so the issue seems to be gone.

Some ideas on where to look for the source:

• AOM issues
• "RF whistling"

There was a similar issue on (70817) where the "OFS servo was saturating" after Detchar injections. The OFS was not happy after troubleshooting this time.

Further investigation is on process.

Opslogin0 web client now working again

Connection to nomachine via web is once again working.

A+ HRTS assembly, balancing and characterization report (for O5)

Ryan C, Austin, Oli, Jeff K, Betsy, Dave, Eric, Fil, RAL/CIT team and Rahul

Happy to report that we have finished the assembly of our first A+ HAM Relay Triple Suspension (HRTS) (freestanding version) with Class A parts as per the assembly procedure described in D1900449_V7.  HRTS is a new small scale triple pendulum suspension required for Balanced Homodyne Detection system. This is first of the twelve suspensions we have to deliver for both the sites (six each for LHO and LLO, which includes one spare per site) for observing run O5.

HRTS comes in two configuration, freestanding (table mounted which is discussed in this alog) and suspended (to be built, will be attached to the new beamsplitter suspension BBSS). The details about the assembly and characterization along with pictures are discussed below,

Attachment01 shows the AR side of the SUS, attachment02 shows the HR side. For isometric view, please see attachment03.

This multistage suspension (three suspended stages) has blade springs at the upper stage and top mass for vertical isolation. There are two blade springs at the very top stage (D2100389) as shown in the picture here. The blade spring are mounted on spring loaded clamps which can be adjusted for Yaw dof and height (sus point). The two wires (diameter 0.006in) from the two top stage blade springs suspends the Top Mass (D2100362) which has four blade springs, as shown here.

Wire diameters are as follows:-

Top Stage to Top Mass = 0.006in, length 115mm

Top Mass to Penultimate Mass = 0.004in, length 115mm

Penultimate Mass to Optic = 0.0025in, length 160mm

Suspended masses (as per specifications):-

Top Mass = 750gm

Penultimate mass = 802gm

Dummy optic = 300gm

The Top Mass blade spring clamps are spring loaded (just like the top stage) which gives them the ability to adjust for blade tip height. We use a tool (T2400063) provided by the RAL UK team for measuring (while adjusting) the blade spring tip height (this tool can only be used for this stage) - as shown in this picture. A calibration block has also been provided for calibrating the tool before using it. The penultimate mass is suspended from the top mass blade springs using four wires of diameter 0.004in. The Optic (dummy optic for now) is suspended using two wires in a loop from the penultimate mass - see picture here. All the wires were pulled using their dedicated wire jigs, which defines the wire length and position within the wire clamps.

We had some issues with wire installation procedure (wires at the top mass stage kinks/breaking too often during handling). After discussions with colleagues here and at RAL we now have a new tool (currently under fabrication) which will aide in wire installation procedure. Also, with practice we are getting better at handling wires of this thickness (thinner than human hair).

Once the assembly was complete, we measured and adjusted the height of the top stage blade springs, which comes out to be 22.5mm from the top plate. This adjustment was made to lower the entire chain such that each stage aligns with their respective position, as marked on the frame. The bottom edge of the dummy optic is now approximately suspended at 40.5mm from bottom of the frame (s/n 002) - which as per the design specifications. The other degrees of freedom like pitch, yaw, roll also looks respectable without any major adjustment, although we can further improve the pitch on penultimate mass (using balance mass and pitch adjuster mechanism provided at two stages).

HRTS is controlled using six BOSEMs, their flag/magnet attachment are as per the controls arrangement document E2300341. After attaching the BOSEMs and with little adjustment all six flags looked nicely centered.

Before centering them we measured their Open Light Current (OLC) and calculated the offsets and gains which are as follows,

BOSEM D060106-E (s/n)	OLC	Offsets (-OLC/2)	Gain (30,000/OLC)
F1 (S1900810)	26807	-13403.5	1.119
F2 (S1900795)	31010	-15505	0.967
F3(S1900754)	30165	-15082.5	0.994
LF(S1900809)	29316	-14658	1.023
RT(S1900782)	28820	-14410	1.040
SD(S1900626)	26768	-13384	1.120

We have a dedicated test stand at the triples lab in the Stagings building, thanks to Fil, Eric and Dave. The hardware (power supply, satellite boxes, Triple Coil driver, IO, AA and AI chassis) can be seen in this picture. We also have a working MEDM screen for HRTS on X1 controls thanks to Jeff Kissel and Oli. Using this infrastructure we started testing out our suspension. The first challenge was too much vibration in the lab due to turbulent air, vibration due to building doors opening/closing etc. Our suspension is sitting on a heavy optical bench and we have also used a teflon sheet for absorbing some of the ground vibrations. However, since the turbulent air in the lab was too much for us to take any meaningful measurements, hence we covered the SUS in two layers of foil and then clean room cloth - as shown over here. We then exited the lab and it took 30mins or so for things to calm down (while HVACs in the lab are still running). Long story short, we took the first top to top transfer function measurements for HRTS and the plots are attached below. I am attaching the DTT plots as well as the ones processed in Matlab.

If you look at the DTT plots, the coherence is not too bad despite all the external vibrations leading to saturations (we have 18bit DAC). In Matlab we can compare our results against the model (Mathematica from M Barton, imported to Matlab). The Longitudinal (L),Transverse (T) and Yaw (Y) dof aligns nicely with the model, ie all peaks and magnitude looks good. Pitch (P) also has most of the peaks at right places (except a missing peak at 4.5Hz), and is off in magnitude which we are investigating. Vertical (V) is noisy (which is expected as the suspension can be easily excited in vertical motion) and has a cross-coupling from Roll (R) (at around 1.8Hz)? Roll (page8) looks the worst of all especially the shape and magnitude at frequency below 2Hz.

I am still fine tweaking the balancing of the suspension, further isolating it environmental noise and discussing with colleagues to take better measurements. In the meanwhile this is a decent start for us, eleven more to go.

Tagging EPO -- Rahul has new babies! This is the newest type of suspension -- and by far housing the smallest triple suspension. So cute!

Changing PRM Position to Improve Build-ups

Jennie W, Jenne

 

Yesterday, on advice from Sheila to we are trying to decouple the alignment changes to IM1, IM3, IM4, PRM and PR2 in this entry from any changes we may be making to the jitter coupling.

So the plan is to move just PRM to the place Gabriele and I had moved it to. This was about 284 counts on SUS-PRM_M1_DAMP_INMON on 22:44:25 UTC on 2024-03-21 when we had being making these changes.

Firstly I did this on the alignment sliders and then realised this is compensated for by camera servo YAW1 which changes the PRM to keep the spot on the BS constant so we need to actually change the camera servo offset to move the PRM.

 

Jenne has turned on ADS lines but we will remain on camera servos for this test and tweak the ASC-CAM_YAW1_OFFSET which will move PRM.

 

We checked the PR2 A2L gain first by injecting lines on PR2 in OSC8 in both and yaw, as Annamaria suggested we would need to check the spot wasn't moving too much on PR2. See first image.

Previous example of tuning A2L gains for PR2 (and I think the last time it was done) are here.

We took a spectrum and changed the A2L gains in SUS-PR2_M3_DRIVEALIGN_Y2L_GAIN to minimise our injected lines in LSC-PRCL_IN1 as these lines did not change much in DARM as we changed the gain.

These were mimimised at P2L gain of -0.31 and Y2L at -7.3 (nominal gain are -0.61 for P2L and -7.4 for Y2L so only the pitch gain changed substantially). Template for this is saved in /ligo/home/jennifer.wright/Documents/Noise_DARM/20240326_PR2_dither.xml.

 

Then I checked the jitter coupling by doing injections using the noise budget templates in:

/ligo/gitcommon/NoiseBudget/aligoNB/aligoNB/H1/couplings/IMC_PZT_{P,Y}_inj.xml after taking a background measurement in each case with the injection off.

We inject into either IMC-PZT-PIT_EXC for pitch and IMC-PZT-YAW_EXC for yaw measurements.

 

The P measurements are saved in /ligo/home/jennifer.wright/Documents/Noise_DARM/20240326_IMC_PZT_P_inj_start.xml

Took Y measurements (no injection and injection) without squeezing as somwething happened to squeezer and it is no longer injected. Saved in /ligo/home/jennifer.wright/Documents/Noise_DARM/20240326_IMC_PZT_Y_inj_start.xml

Moving PRM down in yaw (via camera offset) made build-ups worse but more power on POP B and B. First cursor on plot shows this point.

 

Measurement Times:

PITCH DOF, no injection: 2024/03/26 23:08:40 UTC

PITCH DOF, injection: 2024/03/26 23:12:22 UTC

 

YAW no injection: 2024/03/26 23:22:18 UTC

YAW injection: 2024/03/26 23:33:45 UTC

 

Plots
Top left - dark red is DARM with injection on, yellow is background with inj off.

Top right - blue is cleaned DARM with injection off, red is with injection on.

Bottom left - green and brown are two jitter witness channels with no injection, red and blue are these same two channels with the same injection on.

Bottom right - green and brown are two jitter witness channels with no injection, red and blue are these same two channels with the same injection on.

 

Made jitter better slightly on IMC-WFS_B_I_YAW.

Could not easily improve A2L coupling on PR2 here. Tried running the dither template for PR2 again and changhing the gains but nominal gains was close to optimal where P2L has -0.61 and Y2L has -7.4.

But took jitter references again just for yaw degree of freedom. For plots:

 

Measurement Times:

YAW DOF No injection: 26/03/2024 23:59:10 UTC

YAW DOF Injection: 27/03/2024 00:02:15 UTC

 

Plots
Top left - dark red is DARM with injection on, yellow is background with inj off.

Top right - blue is cleaned DARM with injection off, red is with injection on.

Bottom left - green and brown are two jitter witness channels with no injection, red and blue are these same two channels with the same injection on.

Bottom right - green and brown are two jitter witness channels with no injection, red and blue are these same two channels with the same injection on.

 

After I had reverted the changes on PRM, Jenne did some IM1 and IM3 yaw steps detailed here (of about 20 counts on sliders instead of the 200 counts Gabriele and I were doing before).

From this image where first cursor is PRM change and second cursor is IM1 and 3 change; we can see that when IM1 and 3 were being changed, the PRM was pulled to the same place as I had moved it to but this time it made the build-ups better.

Jenne and I conclude that this alignment change is thus not just the PRC being re-aligned but some input clipping or pointing.

Also in Gabriele and I's moves we only moved YAW after aligning pitch and so this may also make a difference.

These YAW moves in IM1 and 3 also unlocked the IFO so we need to look closer into why this happens (Jenne suggests some fast loop is running away), but I think this YAW alignment is something we should move towards maybe with other changes to make sure all the loops stay stable.

---

Just to clarify we reverted all the A2L gain changes and alignment changes after we lost lock.

EX bias change test

Artem, Sheila

We changed the bias on ETMX while adjusting the drivealign gain to compensate, similar to what was done in 73913.  We might be seeing a small difference in the DARM spectrum between 30-40 Hz. 

We scaled the drivealign gain with the bias, but also adjusted the gain at each step to keep the DARM OLG the same. 

voltage	references	quiet time start (UTC March 27th)	quite time end	DA gain	DA gain scaling (in addition to bias voltage scaling)	OLG change %
140	0-6			184.65	NA	NA
190V	8-13	15:41:40	15:58:51	126.895	0.93	0.5
240V	14-20	16:02:54	16:19:05	96.167	0.89	1
289.6V	21 -27	16:27 *	16:43:30	77.22	0.865	1.2
415	28-34	16:49	16:59:30	51.628	0.829	1.8

People walking in LVEA and plugging in CM board seemed to cause some glitches. no evidence of people walking on seismometers from 16:37 on.

The first attachment shows the DARM OLG after gain adjustments.  The second attachment shows long spectra at the various biases we checked.  We also looked at coherence with the susrack magnetometer (Y)  and ESD power monitor 18 V, and saw no coherences there.

The third attachment shows a comparison of the spectrum with 190V bias and 415V, making it easier to see that there might be a difference in noise.  A next step would be to do some repeated steps between these bias settings to see if the difference is repeatable, and doing a broadband PCAL to DARM injection to check that the calibration is as consistent as we think it is between these settings.

Attached whitened DARM and my ESD noise model spectrograms for different bias levels. Not sure it shows something, in particular for 240V bias there were people walking so there are some glitches (I thought last 6 minutes were quiet - from seismic - but apparently they were not..). 415V bias spectrogram also has some glitches..

Lockloss at 21:15UTC from In-lock charge Measurements

We tried the in-lock charge measurements but forgot about the New-DARM configuration so caused a lockloss in the SWAP_TO_ITMX state.

It seems also that only ETMY was ever moved during the part of the test that did run (I'd expect everything but ETMX measured, because the last one requires switching control to the other TM which caused lock loss). In the measurement last week, it seems excitation was applied on all masses as it should be. Attached are plots from this week and last week.