Camilla C, Brice W, TJ S

Following the procedure written out by Alastair - T1600050 - today we did a full flush of both chiller lines with ~13gal each.

The last time a full flush was done, and not just refills from line leaks or chiller swaps, was back in 2016 (alog30017). This is notably, much longer than the 6mo service interval the manufacturer recommends. Just like back then, after turning off the lasers, power supplies, and AA chassis, we disconnected all electrical and tried to drain the chillers to start. We struggled to get much out of the chiller via the drain pipe, but a trickle would come out of the process input if the ball valve on the back of the chiller is set to a 45deg angle. After the chillers were mostly drained, we tried to wipe the reservoirs to get out any junk that was in there. We then set up a hose with a quick connect and connected it to the process input line and ran it to a bucket below the mezzanine to avoid carrying large quantities of water down those stairs (see attachment 1). The process output was hooked up to the chiller, then with two people on the mezzanine and one below to watch the bucket and hose, we turned on a chiller and filled the reservoir as the level dropped. We put about 13 gal through the system for each before turning off the chiller, which should be more than each system contains (alog30638).

Seperately, I noticed while we were swapping the TCSY laser that some of the 1/4" tubing connected to the RF driver felt softer than others also connected to it. Turns out, 2 of the 8 connected to it are a different type - Tygon 2001 (softer) vs Tygon2475. According to a data sheet I found, the 2001 has a max working pressure of  30psi compared to the 2475 max at 50psi. We should really think about replaing all of these lines post O4, but I'll need to look into how much pressue these lines actually have.

Jonathan, Dave:

The GC UPS went onto battery power yesterday evening at 20:38 and sent email to sysadmin. The MSR UPS did not send email, it went onto battery power for less than one second. The attached mains_mon trend shows that this glitch was seen in the CS-EBAY, but it was a very slight dip in voltage on two of the phases. Perhaps the glitch was more significant in the GC server area.

Fri Oct 25 10:08:35 2024 INFO: Fill completed in 8min 32secs

After we swapped CO2Y in 80812. We used Ryan's updated Rotation Stage calibration code, now saved as /opt/rtcds/userapps/release/tcs/h1/scripts/RS_calibration/CalibRotStage.py
to calibrate the CO2Y rotation stage. I added another argument so we can use the same code and specify --optic ITMX or ITMY. Updated instructions in the README.txt

Current fitting coefficients: 4.16, 1.99, 59.58, 0.0
New fitting coefficients: 6.5377, 1.9908, 60.5383, 0.0179

Accepted in sdf. Requested using power control for 1.7W, got 1.71W output. Then tested with TCS_ITMY_CO2_PWR guardian (includes bootstrapping) and got 1.71W too. Great.

TITLE: 10/25 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Corrective Maintenance
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: SEISMON_ALERT
    Wind: 11mph Gusts, 9mph 3min avg
    Primary useism: 0.09 μm/s
    Secondary useism: 0.25 μm/s
QUICK SUMMARY:

• Pavement patching is underway, no OSB parking
• NPRO swap continues today
• h1pslcam is down

J. Oberling, R. Short, C. Compton, T. Guidry, J. Driggers

Continuing from yesterday, this morning Camilla and Ryan began First Contact cleaning the lenses for our chosen mode matching solution.  I met with Tyler and he modded the spacer plates for us.  Once that was done I went into the enclosure to begin building the new lens mount stack and place the rail for it.  While in there also looked at exactly where on the table our new lens would be going.  In checking this I found a discrepancy in the As Built layout; the NPRO was placed in the wrong position, 1/2" back from where it's actually sitting.  Seeing this, I left the enclosure and re-ran the mode matching to account for this change in distance to Amp1's input beam waist location.  The solution stayed the same but the lens locations changed slightly.  I finished this as Ryan and Camilla were finishing up the lens cleaning, and it was almost lunch time so we broke for lunch.

After lunch, Ryan and I went into the enclosure to start installing the mode matching lenses.  While in the enclosure Jenne (from the CR) and Ryan worked to find the script that Varun wrote back during the '21 laser upgrade to quickly do a Gaussian fit to beam propagation measurements, which will really speed up checking the results of our mode matching; they found the script and it lives in /ligo/gitcommon/labutils/beam_scans.  We then installed L01, an f = +222mm lens, and recovered the beam alignment.  With the new L01 in place we then re-installed the EOM and aligned it.  Next was installing the new lens, an f = -334mm lens now known as L21.  We roughly placed it, then used a scale to measure back from M03 to place it more accurately.  It was at this point we discovered yet another discrepancy in the As Built layout; I had not put the beam path from mirrors M03 and M04 on the correct row of holes, which added 2" to our NPRO to Amp1 distance.  So once again we left the enclosure to take yet another look at mode matching (we have now discussed talking with CDS about getting JamMT on one or both of the computers in the Laser Room; this requires an installation of the Java Runtime Environment); the lenses did not change but their positions did (as expected), see attached.  This done, we went back into the enclosure to install the last 2 lenses in the proper locations for our mode matching solution.

We had to remove WP02, as L21 now sits where WP02 once did (not a big deal, the position of WP02 is not critical).  This done we installed L21 and aligned it; during alignment we had to drive the lens to the furthest extent of the lens mount to align the beam, which should not be the case if our M02 to M03 alignment was good.  Turns out we were checking the alignment at a bad point, beyond M03.  M03 and M04 are used to align the beam into Amp1, so the beam won't be exactly on a row of holes there, but the alignment jig we use (one of the tall posts with pinholes in it at beam height that we stick a power meter behind, then adjust the optic being aligned until power is maxed) sit on a row of holes.  By aligning L01, the EOM, and L21 to a point beyond M03 we were steering the beam off of our previous M02 to M03 alignment.  So we moved the alignment post to in front of M03 and re-aligned L01, the EOM, and L21; things looked much better after that.  Finally we installed and aligned the new L02, an f = +222mm lens.  We stopped for the day at this point.  The final attachment is the new layout between FI01 and M03.

On deck for tomorrow, in order (likely to bleed into the weekend/next week at this point):

• Beam propagation measurements (done with the leakage beam through M03) and any required adjustments to get the input beam waist and position correct for Amp1
• Begin recovering Amp1
• Check everything is still OK between Amp1 and Amp2
• Begin recovering Amp2
• Check everything is still OK between Amp2 and the PMC
• Recover PSL stabilization systems

This alog builds off of the work done by Joshua to measure PR2 and PR3 BOSEM coupling in alogs 80732 and 80814. His injections showed that PR2 coupling to DARM occurs up to about 12 Hz, and PR3 coupling up to 25 Hz. To note: these injections were performed above 10 Hz, and the measurements were able to pick up some coupling between 7-10 Hz as well. However, I think the most significant coupling, and limitation of the BOSEMs likely occurs in the auxiliary controls below 5 Hz. There is some indication of that from these measurements.

I used his injections to investigate the pathways of this coupling. I modeled my scripts after the scripts that Sheila has written previously to measure couplings to DARM through multiple pathways, as in 80730.

I made two plots, one showing each PR2 bosem contribution to DARM and one showing each PR3 bosem contribution to DARM.

There is also a set of plots attached to this alog that show each PR2 and PR3 bosem coupling to DARM projected through MICH, PRCL, SRCL, CHARD P and Y and PRC2 P and Y (PR3 ASC, PR3 LSC, PR2 ASC, PR2 LSC).

Overall, these results indicate that PR2 and PR3 coupling to DARM through ASC and LSC loops are fairly minimal. The PR2 and PR3 noise seems to show up most strongly in RF9, so there is strong coupling to PRCL and PRC2. I predict there is probably coupling to CARM, especially for PR3. As a quick test, I compared the LSC REFL RF9 Q error signals during the injection and saw coupling of the PR3 BOSEM noise up 30 Hz (dtt screenshot, where reference trace shows quiet time, live trace is during the PR3 T2 BOSEM injection).

As an example, I projected the BOSEM noise to PRCL, PR2 projection and PR3 projection (the result is uncalibrated). I think if we injected at even lower frequencies, we would see that PRCL, is greatly limited by this noise.

If we would like to do further tests to investigate this coupling, we should: inject at lower frequencies, open the POP beam diverter to see the appearance of this noise on the POP WFS, and move to 1 CARM sensor to see the appearance of this noise on an out-of-loop CARM sensor. The POP WFS test would help us understand if, for example, this excess noise on PR3 is causing some sort of jitter that couples to DARM. This would help further understand why PR3 BOSEM seems to couple strongly to DARM up to almost 30 Hz, but only appears weakly in the auxiliary DOFs.

However, it is also important to finish investigating the contributions of all triple suspensions, so PRM, BS, and all the SRC mirrors.

I made all of these plots using the utils code from the aligoNB repository. All code, DTT templates and plots can be found in my home directory: /ligo/home/elenna.capote/BOSEM

A new LIGO-designed DAC was installed recently on ETMX L2 (PUM) channels. To assess the noise of the new DAC, I re-ran the PUM DAC noise budget using data from 2024-10-21 23:00 PDT. This DAC noise projection is made by subtracting drive signals from the PUM noisemons.

From the first attached plot, we can see that above 20 Hz, ETMX's new DACs are about 5x quieter than the others, which are General Standards 20-bit DACs without dither. The new DAC noise is similar above 20 Hz to what is seen in L1, using GS 20-bit DACs with dither applied.

Sub-budget plots showing the performance of the individual channels are also attached.

TITLE: 10/24 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Corrective Maintenance
SHIFT SUMMARY: NPRO work continues, other minor maintenance and opportunistic activities during the day as well.
LOG:                                                                                                                  

FMCSSTAT is currently RED on the CDS Overview due to a sharp increase in LVEA Zone4 temperature (around HAM6) at 08:59 PDT. TJ confirmed this was due to powering up a clean room.

A reminder that the FMCSSTAT button on the CDS Overview stays RED for up to 2 hours after the alert to give everyone time to see it.

J. Kissel echoing E. Dohmen

Just a bit of useful info from E.J. that I think others might be interested in (and giving myself bread crumbs to find the info in the future):

- The PRODUCTION (H1 included) systems are only at 5.1.4 with no plans on upgrading soon. 

- h1susetmx computer, however is at a prototype version of 5.3.0 in order to support LGIO DAC testing (see LHO:79735)

- One can find the running release notes for modern versions (since RCG 2.0) of the RCG at
https://git.ligo.org/cds/software/advligorts/-/blob/master/NEWS?ref_type=heads

Vicky, Sheila

Summary:  Today we learned that frequency independent anti-squeezing is a very good way to determine which sign the homodyne angle is. 

Background: I've been working on using code from Vicky's repo and the noise budget repo to do some checks of a quantum noise model, this is in a new repo here. 

Details about how this model is made:

The first attached plot illustrates how these models and plots are made.  It starts with a no squeezing time, and an esitmate of non quantum noises from the noise budget, (dark gray, this one is from Elenna's recent run of the noise budget: 80603  ) and an estimate of the arm circulating power along with other parameters set in a quantum parameters file in the same format that is used by the noise budget.  It fits the readout losses by adding a gwinc model of quantum noise with the noise budget estimate of other noises, and adjusting the readout losses of the gwinc model, this is done from 1.5-1.8kHz in this case.

Based on this readoutlosses we get a model of quantum noise without squeezing, and subtract that from the no squeezing trace to get an estimate of the non-quantum noise.  This is enough different from the noise budget one that I've used that as the estimate of the non-quantum noise for the rest of the traces. 

By subtracting this subtraction estimate of the non-quantum noise, it estimates squeezing in dB, and finds a median level of dB from 1.5-1.8kHz for anti-squeezing and squeezing. This should be the same with and without the filter cavity, but in this data set there is slightly more anti-squeezing in the time without the filter cavity, so I've used FIS and FIAS to estimate the nonlinear gain and total efficiency for squeezing.  The nonlinear gain is translated into generated squeezing for gwinc, and the injection losses for squeezing are set so that the injection efficiency* readout efficiency = total squeezing efficieny. 

With this information we can generate models for anti-squeezing and squeezing traces, but fitting the squeezing angle to minimize or maximize quantum noise.  Then for the mid angle traces, the squeezing angle is fit to minimize the residual between the data and the quadrature sum of the subtraction estimate of non quantum noise and the model. We can then look at these plots and try manually changing parameter in the quantum parameter file.

Homodyne angle:

We've been stumped for a while about the excess noise we see with low frequency anti-squeezing, in 79775  I went through old alogs and see that we've had this mismatch of model with our data for a long time.  Today we tried flipping the sign of the homodyne angle and see that low frequency anti-squeezing is much closer to fit both with and without the filter cavity. Compare the 2nd and 3rd attachments to see this.

We still have more work to do on this model, including adding in the additional traces near squeezing and near anti-squeezing that Camilla took, and checking if it can give us any information about arm power (it doesn't seem very useful for that), or the mode mismatches. 

J. Kissel
WP 12140

I've completed 6 SUS + 4 ISI = 10 of 12 total DOF excitations that I wanted to drive before I ran out of time this morning. Each drive was "successful" in that I was able to get plenty of coherence between the 4 DOFs of ISI drive and SUS response, and some coherence between 6 SUS drive DOFs and ISI response. As expected, the bulk of the time was spent tuning the ISI excitations. I might have time to "finish" the data set and get the last two missing DOFs, but I was at least able to get both directions of LPY to LPY transfer functions, which are definitely juicy enough to get the analysis team started.

Measurement environmental/configuration differences of the HAM2 ISI from how they are nominally in observing:
    - PR3 M1 DAMP local damping loop gains are at -0.2, where they are nominally at -1.0. (The point of the test.)
    - CPS DIFF is OFF. (needed to do so for maintenance day)
    - Coil Driver z:p = 1:10 Hz analog low-pass (and digital compensation for it) is OFF. (need to do so to get good SNR on SUS M1 drive without saturating the SUS DACs)

Interesting things to call out that are the same as observing:
    - The PR3 alignment sliders were ON. P = -122 [urad]; Y = 100 [urad]. (Don't *expect* dynamics to change with ON vs. OFF, but we have seen diagonal response change if close an EQ stop. Haven't ever looked, but I wouldn't be surprised of off-diagonal responses change. Also DAC range gets consumed by DC alignment request, which is important for driving transfer functions.)
    - Corner station sensor correction, informed by the Bier Garten "ITMY" T240 on the ground. (the h1oaf0 computer got booted this morning, so we had to re-request the SEI_CS configuration guardian to be in WINDY. The SEI_ENV guardian had been set to LIGHT_MAINTENANCE.)
    - PR3 is NOT under any type of ISC global control; neither L, P, or Y. (global ISC feedback for the PRC's LPY DOFs goes to PRM and PR2.)

There are too many interesting transfer functions to attach, or even to export in the limited amount of time I have. 
So -- I leave it to the LSC team that inspired this test to look at the data, and use as needed.

The data have been committed to the SVN here:
    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/PR3/SAGM1/Data/
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_L_0p02to50Hz.xml
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_T_0p02to50Hz.xml
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_V_0p02to50Hz.xml
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_R_0p02to50Hz.xml
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_P_0p02to50Hz.xml
        2024-10-15_1627_H1SUSPR3_M1_WhiteNoise_Y_0p02to50Hz.xml

    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/PR3/Common/Data
        2024-10-15_1627_H1ISIHAM2_ST1_WhiteNoise_PR3SusPoint_L_0p02to50Hz.xml
        2024-10-15_1627_H1ISIHAM2_ST1_WhiteNoise_PR3SusPoint_T_0p02to50Hz.xml
            [ran out of time for V]
            [ran out of time for R]
        2024-10-15_1627_H1ISIHAM2_ST1_WhiteNoise_PR3SusPoint_P_0p02to50Hz.xml
        2024-10-15_1627_H1ISIHAM2_ST1_WhiteNoise_PR3SusPoint_Y_0p02to50Hz.xml


For the SUS drives templates, I gathered:
     Typical:
     - The top mass, M1, OSEM sensors, in the LTVRPY Euler Basis, calibrated into microns or microradians, [um] or [urad].
         H1:SUS-PR3_M1_DAMP_?_IN1_DQ             [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The top mass, M1, OSEM sensors, in the T1T2T3LFRTSDD OSEM Sensor/Coil Basis, calibrated into microns, [um].
         H1:SUS-PR3_M1_OSEMINF_??_OUT_DQ         [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The top mass, M1, OSEM coils' requested drive, in the T1T2T3LFRTSD OSEM Sensor/Coil Basis, in raw (18 bit) DAC counts, [ct_M1SUS18bitDAC].
         H1:SUS-PR3_M1_MASTER_OUT_??_DQ          [Filtered with the 32x filter, then downsampled to to fs = 512 Hz]

     For this set of templates:
     - The bottom mass i.e. optic, M3, OSEM sensors, in the LPY Euler Basis, calibrated into microns or microradians, [um] or [urad].
         H1:SUS-PR3_M3_WIT_?_DQ                  [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The bottom mass i.e. optic, M3, optical lever, in PIT YAW Euler Basis, calibrated into mircoradians, [urad].
         H1:SUS-PR3_M3_OPLEV_???_OUT_DQ          [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The ISI's Stage 1 GS13 inertial sensors, projected to the PR3 suspension point LTVRPY Euler basis, calibrated into nanometers or nanoradians, [nm] or [nrad]
         H1:ISI-HAM2_SUSPOINT_PR3_EUL_?_DQ       [Filtered with the 4x filter, then downsampled to to fs = 1024 Hz]
     - The ISI's Stage 1 super sensors, in the ISI's Cartesian XYZRXRYRZ basis, calibrated into nanometers or nanoradians, [nm] or [nrad]
         H1:ISI-HAM2_ISO_*_IN1_DQ                [Filtered with the 2x filter, then downsampled to to fs = 2048 Hz]

Note: The six M1 OSEM sensors in the Euler Basis are set to be the "A" channels, such that you can reconstruct the transfer function between the M1 Euler Basis to all the other response channels in the physical units stated above. As usual the excitation channel for the given drive DOF (in each template, that's H1:SUS-MC3_M1_TEST_?_EXC) is automatically stored, but these channels are in goofy "Euler Basis (18-bit) DAC counts," so tough to turn into physical units.

For the brand new ISI drive templates, I gathered:
     - The ISI's Stage 1 super sensors, in the ISI's Cartesian XYZRXRYRZ basis, calibrated into nanometers or nanoradians, [nm] or [nrad]
         H1:ISI-HAM2_ISO_*_IN1_DQ                [Filtered with the 2x filter, then downsampled to to fs = 2048 Hz]
     - The ISI's Stage 1 GS13 inertial sensors, projected to the PR3 suspension point LTVRPY Euler basis, calibrated into nanometers or nanoradians, [nm] or [nrad]
         H1:ISI-HAM2_SUSPOINT_PR3_EUL_?_DQ       [Filtered with the 4x filter, then downsampled to to fs = 1024 Hz]

     - The top mass, M1, OSEM sensors, in the LTVRPY Euler Basis, calibrated into microns or microradians, [um] or [urad].
         H1:SUS-PR3_M1_DAMP_?_IN1_DQ             [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The bottom mass i.e. optic, M3, OSEM sensors, in the LPY Euler Basis, calibrated into microns or microradians, [um] or [urad].
         H1:SUS-PR3_M3_WIT_?_DQ                  [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The bottom mass i.e. optic, M3, optical lever, in PIT YAW Euler Basis, calibrated into mircoradians, [urad].
         H1:SUS-PR3_M3_OPLEV_???_OUT_DQ          [Filtered with the 64x filter, then downsampled to to fs = 256 Hz]
     - The ISI's Stage 1 actuators' requested drive, in the H1H2H3V1V2V3 ISI actuator basis, in raw (16-bit) DAC counts, [ct_ISIST116bitDAC].
         H1:ISI-HAM2_OUTF_??_OUT                 [Didn't realize in time that there are DQ channels H1:ISI-HAM2_MASTER_??_DRIVE_DQ stored at fs = 2048 Hz, or I would have used those.]

Note: Here, I set the number of "A" channels to twelve, such that both the ISI's Cartesian basis and the PR3 Suspoint basis versions of the GS13s can be used as the transfer function reference channel.