Starting 3:46 UTC

I adjusted H1:SQZ-OPO_TEC_SETTEMP while Watching the H1:SQZ-CLF_REFL_RF6_ABS_OUTPUT ndscope ( OPO temo ndscope found on the SQZ scopes dropdown)  to change the OPO Tec Temp.
ending at 3:50 UTC

Sheila and I discussed doing a SQZ Angle adjustment but it seemed fine at the time.

TITLE: 10/03 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ryan Short
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.26 μm/s
QUICK SUMMARY:

H1 is currently in Nominal_LOW_NOISE[600] with little wind and decreasing secondary microseism.
 

TITLE: 10/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Busy today today, from multiple lock acquisitions to commissioning activities this morning. Unfortunately, not much observing time for H1 today, but's relocking now, currently up to MAX_POWER.

• 14:30 - H1 relocking
  • 15:05 to 15:28 - Ran initial alignment
• 16:38 - Reached NLN (fully automatic relock), starting planned commissioning activities
  • 17:57 - ISI HAM7 WD trip from activity near chamber
  • 18:27 - Lockloss - alog80443
  • 18:46 - HEPI HAM1 WD trip from activity on chamber
• 20:46 - Reached NLN, but SQZ needs work so waiting start observing
• 21:49 - Observing
• 22:19 - Lockloss - alog80453

LOG:

Lockloss @ 22:19 UTC - link to lockloss tool

No obvious cause, but it looks like the IMC lost lock at the same time as the arms. However, I don't suspect the FSS in this case.

Sheila, Camilla. WP 12116, 12117. Last done in October 2023: 73524.

Followed instructions from 73524, 65684, with additional notes below. 

Took SQZT7 area to local laser hazard and plugged straight into the OPO_IR_PD for our red signal and the OPO_TRANS PD for our green signal. Trying to take the signals from the outside of the table or the SQZ racks was confusing. 

Setup:

• Old style function generator, offset 4.5V for a 1-9V scan at 10Hz.
• Oscilloscope and long BNCs/adapters: plug into function generator, OPO_IR_PD and the OPO_TRANS photodetectors inside SQZT7. 
• PZT driver MDT694 which has 0-150V output for 0-10V input, connected this to the PZT1 connector in the back of the chassis, using the adapter for PZT2 (note this means that the PZT2 offset we had been keeping at +10V was 0V for this measurements, controlled by CLF SLOWOUTOFS 65535). 
• Wincam dell laptop and gray E-870 PI shift driver box (stored in LVEA SQZ cabinet) and the OPO crystal cable remains attached +X HAM7 flange.

What we did:

• After set up once we could see both mode scans on the oscilloscope, we injected the seed beam and reduced green power from 30mW to 6mW to avoid pumping too much. Pico wasn't working: 80449.
• Adjusted temperature to get red and green co-resonance. Plot attached of before spot move. 
• In alog 73524 we used the OPO spot 2nd from the left. We moved (32 x 50 steps to right, then 2 x 10 steps to right) to the next spot with a red-green co-resonance, 3rd from the left. Plot attached.
• Increased the green power back to 25mW, then 30mW and then things got confusing: we were seeing rapidly changing strange signals and negatives on OPO_TRANS channel. Beckhoff version of the channels looked better. We eventually found that the whitening filters must have been saturating and giving us strange signals. We increased SHG ISS drivepoint to 10V, allowing us to use a lower green pump, this showed that the high green pump was our issues. Then reduced the SHG power to 14mW while the SHG ISS drivepoint was in the middle of the range at 5V. When the ISS was engaged, it could keep the opo_grTrans_setpiont_uW to 80uW with the controlmon around 6 and SHG_LAUNCH ~11.5mW. This is much less than the 30mW we needed this morning so this new crystal spot is much less lossy. 
• OPO started to oscillate when we locked it so we reduced the OPO gain from -4 to -8 and accepted in sdf.
• Sheila set the opo_grTrans_setpiont_uW to 80uW in sqzparams.py and we measured the NLG to be 11 (Amplified / Un-amplified = 0.098/0.0089 see 76542).
• Ran SCAN_SQZ_ALGNMENT and SCAN_SQZ_ANG. This gave us >4dB of squeezing at high frequency.  
• We left PZT2 (CLF SLOWOUTOFS) at 0V, see 80450.

Today, 75uW OPO trans power corresponded to 0.945 on the OPO refl diode, last night that was 4.161mW on OPO refl diode. Meaning after this spot move we now need to inject a lot less power into the OPO to get the same output power.

Camilla and I ran SQZ_ALIGNMENT and SCAN_SQZ_ANG with the offset on PZT2 (we are using H1:SQZ-CLF_SERVO_SLOWOUTOFS) set to 0, while the nominal value is 10.  We then went to no squeezing and set the offset back to it's nominal value, and saw reduced squeezing when we reinjected squeezing.  We could recover the better squeezing level by slowly stepping this offset back to 0V.  We think that this could be because the PZT setting changes the alignment of the OPO, and the squeezed beam coming out of it.  (which also changes the squeezing angle). 

A similar effect was seen with PZT1 in 80396 and 78529.  It would be interesting another time to try changing this offset and seeing if we can recover squeezing by readjusting alignment and squeezing angle.

The picomotor to adjust the OPO pump power is not working, H1:SYS-MOTION_C_PICO_I_MOTOR_2.  When someone commands the waveplate to turn from medm, there is a clicking sound on the table that seems to come from the rotation stage, but it doesn't move. 

We need to adjust this by hand for now if the ISS runs out of range (or alternatively, we can change the ISS set point).

FRS: 32288

Lockloss @ 18:27 UTC - link to lockloss tool

Happened at the end of commissioning time while PRCL NB injection was being run, although I don't suspect that as the cause. There was also work happening near HAM7 and the SQZ tables. Only thing in the trends I notice is some motion in ETMX L3 and DARM as the first action; hard to tell which happens first. No other obvious cause, including the FSS.

The FSS was very unhappy when trying to relock the IMC after this lockloss. I needed to toggle the autolocker a couple of times before the glitching calmed down enough to allow the IMC to lock.

After a failed test of the "correct" PRCL feedforward fit today (80444 and 80287), I tried again to fit a PRCL feedforward, this time using the good measurements Camilla took in 80444, using both the PRCL excitation and the correct PRCL preshaping.

There was some trial and error here, mainly due to the difficulty in matching the phase as well as the rising gain of the transfer function above 100 Hz, which you can see in this plot. This results in the best fit having some high Q pole just above 250 Hz, and of course the usual struggle to keep the gain low below 10 Hz. I found better results when I limited the gain between 1 and 10 Hz to a maximum of 0.5, and also reduced my fit range to go between 10 and 60 Hz, which is where the sensitivity improvement is required, and then limited the gain from 100-1000 Hz to 0.02. PRCL is limiting the noise up to 30 Hz, and far below th noise floor around 100 Hz, so it's probably ok to keep the PRCL noise the same or just slightly worse above 60 Hz (NB alog).

Finally, with Gabriele's help, I found a fit that worked! Here is the injection comparison with no feedforward and the new feedforward. I updated the DARM traces, so you can see that the PRCL contribution to DARM is slightly worse around 100 Hz, but much better up to 60 Hz, by up to a factor of 10.

The new filter is in FM7 (I have triple checked this!) and I have added it to the guardian and SDFed this in observe (screenshot).

I did some chopping of the PRCL FF to check the improvement in DARM, see plot. I think there is improvement between 20-30 Hz, but it's hard to tell.

I set out to rerun the noise budget injection of PRCL so we could remake the plots, but there was a lockloss while I was measuring (I think because people were on the floor?). I don't think the lockloss was from the NB injection.

Thu Oct 03 08:09:57 2024 INFO: Fill completed in 9min 53secs

Jordan confirmed a good fill curbside.

It is getting colder outside, I've increased the trip temp from -110C to -100C.

TITLE: 10/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 5mph Gusts, 3mph 3min avg
    Primary useism: 0.05 μm/s
    Secondary useism: 0.30 μm/s
QUICK SUMMARY: H1 just lost lock about 15 minutes ago; will start looking into it shortly, although the cause may be from a recent earthquake out of Japan.

• Wind is low, microseism trending down
• All other systems nominal

TITLE: 10/03 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY:

Another Lockloss @ 1:23 UTC 

Relocking was rather difficult even after an Initial Alignment due to the IMC goining into fault because the FSS.
I eventually took ISC_LOCK to Down. and the PSL FSS to Down and the IMC to Down. and then requested Nominal_Low_Noise from ISC_LOCK. IDK it just seemed to work for me. your milage may vary.

Once the FSS decided to play ball, the rest of Locking went well enough.

Observing reached @ 3:25 UTC and with out any notable incidents .

The IFO has now been locked and Observing for 1 hour and 43 minutes.
 

LOG:

TITLE: 10/02 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 21mph Gusts, 13mph 3min avg
    Primary useism: 0.08 μm/s
    Secondary useism: 0.45 μm/s
QUICK SUMMARY:

Sudden Lockloss @ 21:55 UTC very likley cause by a PSL FSS issue.

IMC Had a hard time relocking locking after the lockloss.

NLN Reached @ 22:54 UTC
Observing reached @ 22:56 UTC

Gerardo, Jordan, Travis, Janos

Reacting to the issue in aLog https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=80370, the HAM1 AIP was checked for controller and pump failures. After trying a couple of controllers, it was clear that the pump broke down.
Shortly after the maintenance period, because of the high seismic activity, locking was impossible, so the vacuum team took the opportunity and swapped the pump (as normally it would have been impossible during the 4 hours of the maintenance period).
The AIP was swapped with a noble diode pump - this was not exactly intentional, but turned out to be a happy accident, as it seemingly works much better than the Starcell or even the Galaxy pumps. However, as the noble diode pump has positive polarity, a positive polarity controller was needed: the only available piece is an Agilent IPC Mini (see it in the picture attached), which works well, but in the MEDM screen it appears to be faulty, due to its wiring differences.
All in all, the HAM1/HAM2 twin-annulus system was pumped with the 2 AIPs and an Aux cart - Turbo pump bundle. The noble diode pump stabilized very nicely (at 5-7E-7 Torr, which is unusually low), so eventually the Aux cart Turbo pump bundle was switched off - at 6:55 pm PT.
Since then, the 2 AIPs continue to decrease the annulus pressure, which is indeed very nice, so practically we are back to normal.
In the meantime, Gerardo quickly modified an appropriate Varian controller to have positive polarity, so at the next opportunity the vacuum team will swap it with the Agilent controller, so the MEDM screen will also be normal. Note that the Aux cart - Turbo bundle remain there until this swap happens.

Yesterday afternoon until 2 am, we had low range because the squeezing angle was not well tuned.  As Naoki has noted 78529 this can happen when the OPO PZT is at a lower voltage than we normally operate at. This probably could have been improved by running SCAN_SQZANG. 

I've edited the OPO_PZT_OK checker, so that it requires the OPO PZT to be between 70 and 110 V (it used to be 50 to 110V).  This might mean that sometimes the OPO has difficulty locking, (ie, 76642), which will cause the IFO to call for help, but that will avoid running with low range when it needs to run SCAN_SQZANG.

I tried Elenna's FM6 from 80287, this made the PRCL coupled noise worse, see first attached plot. 

Then Ryan turned off CAL lines and we retook to preshaping (PRCLFF_excitation_ETMYpum.xml) and PRCL injection (PRCL_excitation.xml) templates.  I took the PRCL_excitation.xml injection with the PRCL FF off and increased amplitude from 0.02 to 0.05 to increase coherence over 50Hz. Exported as prclff_coherence/tf.txt, and prcl_coherence/tf_FFoff.txt. All in /opt/rtcds/userapps/release/lsc/h1/scripts/feedforward

Looking at data from a couiple of days ago, there is evidence of some transient bumps at multiples of 11.6 Hz. Those are visible in the summary pages too around hour 12 of this plot.

Taking a spectrogram of data starting at GPS 1410607604, one can see at least two times where there is excess noise at low frequency. This is easier to see in a spectrogram whitened to the median. Comparing the DARM spectra in a period with and without this noise, one can identify the bumps at roughly multiples of 11.6 Hz.

Maybe somebody from DetChar can run LASSO on the BLRMS between 20 and 30 Hz to find if this noise is correlated to some environmental of other changes.