Jennie W, Keita K, Jason O, Jenne D,

Once we got the locking of JAC and IMC working at 20W this morning, Keita went into the chamber while we had PRMI aligned to check the POP beam alignment in HAM1.

We had trouble keeping the IMC locked when Keita was moving next to the chamber, JAC occasionally unlocks but is staying locked for long periods. I hypothesise that JM3 moving around is more of a problem than JM1 because of this. Eventually we managed to stay locked with 4W while Keita was in chamber. Over this period Keita realised the beam was mis-aligned coming out of the POP periscope and so we used PR2 and PR3 yaw to walk the beam back till it was well centred on AS AIR camera and we still saw flashes. Eventually we mis-aligned ITMY and just used PRX flashes. We had to move 10 microradians on PR2 and then correct with 1 microradian on PR3 to maintain the alignment.

I put the power up to 10W from 4 W and we saw a power change on ASC-POP_X.

To see if we could recover alignment onto POP-X with PM1 we put the PM1 yaw up to a high value so it was railing and we did see some counts on ASC-POP_X QPD SUM but we cannot point the beam onto the diode before PM1 rails so we undid this.

The day ended with a total move of -120 on PR2 yaw, -12 on PR3 yaw, -8.1 mircoradians on PR3 pitch, and +81 microradians on PR2 pitch. Keita can now see the beam on the side of the ASC POP X QPD.

The pitch changes we did at the end of the day were to try and improve the steering to ASC POP X but we didn't get time to optimise this so we can undo them tomorrow if necessary.

Summary: Checking POP is hard as the IMC will unlock very easily if someone is in HAM1, probably due to shaking of JM3. We need to work out if we trust the PRC alignment axis or if we want to cross-check it with something else (like the ALS beam from the X-arm) before we continue debugging.

(Jordan V., Travis S., Gerardo M.)

We removed and replaced the broken pressure regulator for GV7, we haven't tested the new regulator yet (open or try to hard close GV7), but hope to do so soon. During the regulator replacement we installed an isolation valve on the line that feeds GV7, this for upcoming work on this system.
While doing the replacement of the regulator for GV7, we discovered that the pressure regulator for GV8 pneumatic system is broken too, currently it is reporting a max pressure of 100 psi and a low pressure of 80 psi, it rides the instrument air compressor behavior (high and lows).  We tried to lower the pressure but the regulator is non-responsive.  We'll replace the pressure regulator at the next opportunity.  Also, it turns out that the pressure regulators attached to the different pneumatic gate valves are not the same model.

Following the B13, B2H34 and H12 upgrades in Dec 2025 and Jan 2026 today I did a second round of verification that the IOP models were reading the correct ADC channels and that the MEDMs were correct. The IOP models are correct and no changes were needed.

Some MEDMs had white-boxes for the raw ADC counts, which was addressed. The SWWD MEDMs use macro file substitution for the detailed screens, and the differences that now exist between the sites means it is no longer feasible to maintain these files in the cds/common/medm/ area. Today I moved them to cds/h1/medm before making the final updates.

At this time all the MEDMs are correct with the exception of the BS IPC channel for SUS-BS to SEI-BSC2. h1iopsusb2h34 has a simulink copy-paste error, the channel which should be BS_WD_SND but is actually BS_WD_SND1, hence the white-box.

I'm also reminded that during these upgrades we decided to not change the IPC channel names in order to minimize the scope of work, so IPC names containing B123, H2A, H34 still exist. During the next RCG upgrade we will correct the names.

An overview of the SWWDs at both sites can be found in the DCC T2600106

TITLE: 03/31 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

Lots of subsystem work going on today.  The JAC team continued their alignment work at HAM1.  SQZ team continued alignment work at SQZT7 and then in the Control Room.  SPI team was in the Optics Lab most of the day.

Tomorrow morning a new HEPA fan will be installed for the h1psl room's anteroom....so it shouldn't affect HAM1 work.
LOG:

• 1411-1500 LVEA technical cleaning (nellie.kim)
  • Held off cleaning top of HAM3, since HAM3 was unlocked  (they noticed the signs saying so at HAM3), AND bifurcated Laser Safe requires goggles at-height, but that makes it unsafe to see things when climbing on top of a chamber.
  • 1515-1635 EY & returned to get keys! (nellie)
    • 1635-1648 FCES (nellie)
  • 1629 Kim out of lvea
    • 1718 EX cleaning
• 1445-1535 handrails on eMod platform (randy)
• 1516 Opening light pipe (sheila)
  • 1519 NOTE:  Sheila noticed a small puddle around the entry to the LVEA (under chiller piping?).  She wiped it up, but would like spot to be checked later.  There was cleaning in lvea earlier.
    • This is most likely just  from cleaning/mopping earlier (richard & kim checked)
• 1535-1540 Optics Lab pop-in (camilla)
• 1540-1618 climbing HAM3 for LO1 (fil)---->PR2, MC2 to SAFE
  • 1618-1730 susR2 work near HAM3 (fil)
• 1544-1606 Opening -Y cloth cover for in-air JAC & locking (jenne)
• 1547-1620 Monthly fire pumps run (eric)
• 1548-1614 both mids for inventory (jordan)
  • 1614-1618 PCal Lab room inventory (jordan)
• 1613-1800 LN2 truck MX
  • ~1645-1811 LN2 truck at Corner's CP1
• 1615-1620 Taking First Contact to flamable cabinet (ibrahim)
• 1616 BHSS work (elenna.camilla)
  • 1623 oli joining
  • 1857 Out for lunch, laser SAFE!
• 1627-1645 Checking on fil (richard)
• 1634-1725 lvea Receiving and then to MX to grab a BS container (ibrahim)
  • 1725 continue BS container search in optics lab (ibrahim)
• 1658-1912 GV7 regulator (gerardo.travis.jordan)
• 1703 Grabbing nd filter in optics lab & taking to IOT1/JAC table (jennie)
  • 1809-1920 Grabbing another nd filter to use at IOT1 (jennie.sheila)
• 1721 turning down purge air down at HAM1, checking rack (keita)
• 1804-1814 PCal (tony)
• 1808-1816 Rosalind Franklin Elementary in Control Room Group1 (amber)
  • 1830--1842 Rosalind Franklin Elementary in Control Room Group2 (cassidy)
• 1914-1932 TCS Chiller maintenance check (corey)
• LUNCH Note:  IMC locking, JAC locking---> next check on beam
• 1958 BHSS Work continues in laser hazard (elenna.oli)
• 1958-2001 quick trip to CER for dustmonitor (ryanC)
  • 2056-2100 Another dust monitor trip (ryanC)
• 2006-2259 SPI work in (jim, sina)
  • 2020 Jeff joining
  • 2124 Jeff returning again
  • 2255 Jim & Sina out for assistance with the in-vac picomotors
  • 2319 Jeff out for the day
• 2006 JAC work at HAM1 (keita, jennie)
  • 2037 jason joining
• 2007 HAM1 photo & then optics lab (josh.georgia.michele)
• 2031-2200 Grabbing HEPA Ceiling Fans from the H2 PSL  room in the LVEA (tyler.eric)
  • 2138 eric out
  • Plan to install one in H1PSL tomorrow (Wed) morning
• 2105 Back to susR2 rack near HAM3 (fil)
• 2114-2232 SQZT7 work (sheila.georgia.sophie.camilla)
  • 2233 sheila and camilla continue sqz work in control room
• 2153-2203 Touching base with JAC crew at HAM1 about a possible guardian change (jenne)
• 2225 Elenna checking to see if she can help the HAM1 crew on Betsy's request
• 2259 SPI crew (jim.sina) asking keita (at HAM1) about picomotors 

Addressed TCS Chillers (Wed [Mar4] 1242-0105pm local time) & CLOSED FAMIS #28559.  (Last checked 28558). 

For measurements below, measuring from "top" of the red floaty ball.

• TCSx Chiller:  Had level of 30.4 cm.  Added 0mL for 30.4cm.
• TCSy Chiller:  Had level of 9.5 cm.  Added 325mL for 10.5cm.  
• There was no water in the small cup under the slow leak.

Due to a mistake in past CHETA models there is more astigmatism then expected on the tables and a change in beam size at the ITM. The astigmatism can be fixed by rotating L1 around the vertical axis and the beam size can be changed by movind L2 using the translation stage in each setup. Using a modified Fintrace model the required rotation angle and translation for each table  as they are currently populated at LHO (0922, 0918) and LLO (0919, 0851) have been calculated and are shown below. 
The tables below give the current astigmatism and then the angles and translations such that the x and y beamsize on the ITM is 52.7mm with no astigmatism. 

This code is avaliable in the CHETA modelling repository.

Without translating of L2 astigmatism can be removed but the beam size is still unoptimised.  

Sheila, Keita, Jennie W, Jenne D, Georgia B.

We want to be able to power up to 20W in JAC to check the POP beam.  

We were loosing lock with about 8W into JAC because the REFL shutter was closing.  Jennie Wright measured 6mW on the REFL diode with 2W input to HAM1 and JAC unlocked yesterday.  This corresponds to 0.58V on the shutter trigger diode.  The threshold cannot be set above 2V, which means we would unlock when 21mW hit the diode.  Jennie Wright added a ND05A into the path before the refl diode, and another ND05A in front of the shutter diode.  

Now, with 2W input to HAM1 and JAC unlocked, we should have 2mW on the REFL diode, and the shutter diode votlage is 0.18V.  The threshold of 2V now will shut the shutter with 22mW on it. 

Gaurdian changes:

The JAC error signals are normalized by the PSL input power if we use the laser power guardian to change the input power, so we shouldn't need a power scaling like 89708.  People have been using the rotation stage instead of the guardian to adjust the power because the laser power guardian would go into fault if the power was below 1W (people have been going below 1W while HAM1 is vented.)   Jenne Driggers adjusted the fault in LASER_POWER and added a 200mW state to the laser power guardian, so now we should use this guardian whenever we want to change powers, even below 1W. 

We also hard coded the gain used for locking JAC in the down state, although this could be reverted to allow the power normalization to work again, once that has been updated to take into account the new ND filters.  Once this was done, we could lock JAC at a variety of powers and also change the requested power after it was locked. 

Georgia B and I also had a look at the IMC guardian, which has not generally been able to lock the IMC except at 2W.  There was some code in the down state of IMC LOCK that was supposed to adjsut settings for lcokign at different power levels, these were unused except for the IN1 gain setting used for acquisition.  Georgia and I adjusted some of these numbers and watched if the IMC would lock, we didn't take much time to test it but we did once twice see the IMC lock with 10W + input power, so that is promising. 

Locked with 2W input, JAC REFL A LF  signal was constantly railing regardless of the purge air level. Turns out that we were using two stages of 1:10 whitening.

I went to the floor and turned one stage off on the front panel of the RFPD DC interface D1102079 (circuit diagram D1102060) in ISC R1 rack and disabled the corresponding dewhitening filter. I could have disabled both, but with an ND0.5 filter JennieW was installing, this will do the job for now.

I always forget this but gray switch up=1 stage active, middle=2stages, down=0.  I put two labels on the front panel so I don't have to remember.

Tue Mar 31 10:10:46 2026 INFO: Fill completed in 10min 42secs

FAMIS Link:  39344

Only CPS channels which look higher at high frequencies (see attached) would be the following:

1. ITMy_ST1 H3
2. ETMy_ST1 H2

In the bash window we get this note:

"BSC high freq noise is elevated for these sensor(s)!!!:       BSITMy_ST1_CPSINF_H3 "

TITLE: 03/31 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 2mph Gusts, 1mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.11 μm/s 
QUICK SUMMARY:

From the alog, it sounds like HAM1 checks will continue; when this is done the move will be  venting the corner and prepping for opening HAM2+3 (and dome next week...but no need to get ahead of ourselves); also when HAM1 work is done, hard close GV2 (x-arm).  SQZ work also continues.

Chilly sub-32degF out.  LVEA door says "laser safe", but from Ibrahim's emails yesterday & alog activity, it is the LVEA is in LASER HAZARD BIFURCATED at HAM1.

Highlights include ndscope combined file and DAQ channel completion on the command line.  Timeout to lock screen should be fixed so that the workstation won't lock you out after a few minutes.  You may need to go into Settings->Power Manager->Display and Settings->Screensaver to turn them off.

This was an OS packages update.  Conda packages were not updated.

Jennie W, Keita K, Betsy W, Camilla C

At the end of the day (for the day's activities to get to this point see Sheila's alog #89701) we were in chamber trying to see PRMI flashes in the POP in-vac path on -Y side of HAM1. We tried to lock JAC at 20W input so the flashses would be clearer on the card but it turns out anything over about 5W input puts the trigger PD above its threshold so the shutter in front of the JAC REFL PD and JAC WFS QPDS closes. Keita had Camill and I measure the power and for 2W input we get 5-6mW on this REFL PD and around 3mW on each QPD. This means that we shouldn't try and raise the trigger threshold (currently at 1.2V) as at 20W we will have 50mW on the REFL PD. I thought we had more of a margin than this.

What this means is we want to lock the JAC every time at 2W and then scale the gain in lock so only a low level of power goes to the REFL PD.

I copied some code from the ISC_library to do this. The new function is the state decorator JAC_pwr_adjust_function. It should scale the gain in JAC-L_SERVO by the requested input power as measured at IMC-PWR_IN_OUTMON while the JAC-LOCK guardian is in the 'LOCKED' state. It compiles now but I haven't tested it on the IFO yet as we left IMC and JAC in down, the input power at 100mW and the lightpipe closed at the end of the day.

This morning I noticed that the oil temp for the Kobelco was high at ~150F (nominal is around 110-115F). Looking at the sight glass for the oil level, it was high compared to it's usual level during operation. (see attached, off line is when compressor is off, RUN is the level during operation)

Gerardo and I confirmed the oil pump was running and the oil line pressure was ok through the control panel. We then opened the ball valve for the coolant line which goes to the oil cooler. This very quickly dropped the oil temp back to nominal, and there was some tuning done to keep it at ~115F.

Gerardo then contacted the rep who replaced the oil pump on this unit a couple of weeks ago, and confirmed it was just a matter of adding more coolant flow to the oil cooler. The oil level at the sight glass then returned to it's nominal level. 

No issues since, but we will continue to monitor.

Sheila, Camilla, Sophie

Following Sheila's finding last week that the nominal ZM2 PSAMS settings of 3.15 V is giving us an oval beam, 89675, we set ZM2 PSAMs to 4.5V and immediately got better flashes in green and IR on FCES. Moved ZM2 to increase flashes to be  ~55 on green PD C and occasionally up to 1.2 on IR PD D with CLF injected.

Sheila could lock green FC for ~10 seconds. With the SEED injected it did not seem to be co-resonant and she needed to turn off SUS feedback to help green FC locking. 

We then locked FC servo (wouldn't stay locked for long, but was able to move FC1, FC2 and ZM2 PSAMS to maximize the maximum locked values. Got to 58 on PD FC_TRANS_C for 4.8V or 4.9V. Leaving at 4.85V. Could further increase to 66 on PD FC_TRANS_C iteratively with FC1 and FC2, see attached. Locked for ~20 s max. 

To get light (100e-6) on SQZT7 OPO_IR PD, we needed to move ZM3 +100urad in PIT on the sliders. 

I then thought that we could go to the location we have SQZT7 IR light and light on the HAM7 WFS and movve ZM3 towards the place where we have known FC flashes and bring back the alignment on the HAM7WFS with ZM2 and FC1. I did this but it maybe unsurprisingly didn't;t work. In hindsight maybe I could have used a different combination of mirrors. 

To get light (100e-6) on SQZT7 OPO_IR PD, still needed to move ZM3 +100urad in PIT on the sliders. At which point there is no flashes on FCES green or IR. to get max light on the SQZT7 PD (0.0018) I had to change ZM3 from P,Y (-474, -367) for FC flashes to  (-334, -309) for SQZT7 light OR move ZM2 from P,Y (429,132) for FC flashes to  (-747,1) for SQZT7 light and centered WFs (not inc. WFS A PIT). In going from SQZT7 light to towards FC light, the beam on HAM7 WFS moves positive in PITCH and positive in YAW. This corresponds to 

I changed  H1:SQZ-RLF_QPD_A_SEG_3_VOLTS  from 1.31087 to 10 to stop this broken WFS A QPD segment from effecting the position on the WFs so much.  Didn't make much of a difference though.

TITLE: 03/30 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

IFO is in IDLE for PLANNED MAINTENANCE

HAM 1 team has been working on JAC from the bifurcated HAM1 area and the control room throughout the day. SPI and BHSS work continued in the optics lab.

IX has been a bit finicky and tripped the SW WDs. They didn't seem like they were untripping and we were seeing the counts get worse with the damping loops. Additionally, the rocker switch death flashed a few times. Jim fixed this by turning off SUS damping, then letting the ISI damp until counts visibly went down before turning on damping everywhere.

BSC2 platform work and HAM3 cabling continued.

LOG:

Jenne Driggers, Sheila, Keita, Camilla, Jennie Wright, Rahul

We are searching for PRX flashes to use for the POP path work in HAM1.  

We are using a DRMI locked time from March 14th (1:30-2 UTC) as a reference.  Since that time HAM2 hepi has been locked, causing a +3.7urad shift in RZ, which means that PR3 and PRM osems need to be -3.7urad yawed compared to how they where before HEPI was locked to reproduce the alignment (this shift is small compared to the misalignments that we are looking for).  

While trying to restore to this reference time, we see that restoring ITMX sliders restults in optical levers similar to the reference time, and PRM sliders results in PRM osems similar to the reference times.  However, restoring PR3 sliders to the reference time gives top mass osem pitch -20 urad in pitch, and PR2 sliders restored gives a +30 urad shift according to the top mass osems.  

HAM2 CPS RY shows a +1.3 urad shift at the same time as the PR3 osem shift show -24urad (these are opposite directions), HEPI shows -1.5urad RY, at 11 am pacific time Friday, there is no change in the DAC drive at this time.  

PR2's shift seems to have happened right after the DACKill from Friday.  Ibrahim and Oli are running top mass to top mass TFs for health checks on both of those.  

Keita walked aligments to get PRX flashes back.  In the end, PRM and ITMX are back to where they were when DRMI was locked March 14th, as well as PR3 yaw.  PR3 pitch osem is back to where it was on the 14th, but the slider is +11urad.  PR2 pitch slider is -47urad, osem says -29 urad, yaw +45 slider, +55 urad osems.  

We dedicded it was time to move on with the in chamber work, because while these alignment shifts are strange, they probably can't explain the misalingment between the in air and the in vacuum pop paths.  

Commissioners wanted health checks run for PR3 and PR2 to check for any suspension issues. I ran TFs for PR3 and Ibrahim ran them for PR2. Results for both suspensions look good. Results for PR3 are below, and then Ibrahim will be commenting on the info for the PR2 measurements.

Settings:
- PR3 in HEALTH_CHECK
- DAMP OFF (including estimator damping)

Data:
/ligo/svncommon/SusSVN/sus/trunk/HLTS/PR3/SAGM1/Data/2026-03-30_2115_H1SUSPR3_M1_WhiteNoise_{L,T,V,R,P,Y}_0p02to50Hz.xml
r12986
Results:
/ligo/svncommon/SusSVN/sus/trunk/HLTS/PR3/SAGM1/Results/2026-03-30_2115_H1SUSPR3_M1_ALL_TFs.pdf
/ligo/svncommon/SusSVN/sus/trunk/HLTS/PR3/SAGM1/Results/2026-03-30_2115_H1SUSPR3_M1.mat
r12987