Friday Ops shift report.

TITLE: 08/07 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:
Dust levels for H1:PEM-CS_DUST_LAB1_300NM_PCF is climbing up to 70,000 counts today. I imagine that the Dust level is goign to continues to rise with the wind this weekend. 

Input Alignment team has a PLAN, which is a simple matter of just walking the mirrors.  

Output  Arm team has been looking for MAXIMUM_POWER through their straws in HAM7, Note: Removed yellow View Port cover and left a guillotine in place on HAM6  & Misaliging SR2 & SR3.  

VAC team reports:  "Cryo Traps are open to the Beam Tubes." &  "The Corner station is still isolated from the Beam tubes." 

End Station Y had it's PCAL Integrating sphere returned today after it was stolen for some lab measurements last night. 

LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:53	FAC	Kim	LVEA	n	Technical cleaning.	15:35
15:30	VAC	Jordan	LVEA	n	Taking pics of GV6 status	16:00
17:12	SQZ	Sheila & Ryan S	LVEA	YES	Power measurements In HAM7	19:42
18:29	VAC	Jordan & Mitchel	LVEA	y/n	opening ION pumps in the LVEA	19:14
19:49	PCAL	Tony, Cory	PCalLab, EY	YES	Taking Ey's PCAL Sphere back to EY's Laser Enclosure.	21:05
20:01	FAC	Tyler +1	EY	-	Wellhead work	22:01
20:24	CDS	Marc, Caroline	CER	-	Swapping ISC power supply	21:04
20:26	PEM	Carlos, Shrey, Miranda	Overpass	-	Seismometer tests	22:26
20:37	VAC	Jordan	LVEA	-	Opening/closing GVs	22:25
21:08	SQZ	Sheila & Ryan	LVEA HAM7	YES	Power Budget measurments & Beam Profiling	23:08
22:09	CDS	Dave	CER	N	Looking at the accelerometer.... Specifically Not Touching it	22:25
22:35	CDS	Dave Miranda	CER	N	Checking on more accelerometer chassis cabling	23:15
22:43	VAC	Jordan	LVEA HAM6	yes	Isolating turbo pumps, and turning on the ION pump in HAM6	22:54

PCAL Receiver Spheres Romoved from End Stations!

Both End Stations had their  PCAL Reciever modules pillaged for Integrating spheres. They were taken to the lab and measured against PS4 on the lab bench for the first time in..... at least 4 years. 
Preliminary Results found here: PSEYRX
And Here: PSEXRX.

Set up notes:
python pcalRRSO4_measure.py \
    -DN1 PSEXRX \   <-Power Sensor  from EX's Receiver side.
    -DV1 8018023 \  <- This KVM is getting the signal that we usually get a temperature signal from.
    -DN2 PS4 \ <---- this is nominal 
    -DV2 8002111 \ < - nominal
    -DT2 1421891 \ <-nominal 
    -a yes \
    -x \
    -log 'PSEXRX_PS4 PSEXRX front track PS4 on the rear track' \

These measurements were ran without a temperature measurement as they do not have an AD590 to read from. But rather the script just assumes the temperatures for both spheres are the same and just used PS4 temperature sensor.
I used the PS5 Kit to set them up (Satelite box, cable, & accessories.) plugged in exactly the way I'd set up PS5.
Read the Voltage off of what would normally be the temperature KVM as it is nominally plugged in. The reason for this is because I was surprised to see that the KVM that we would normally get temperature signals from PS5 with would change voltage readings when the Sphere was exposed to Laser light....  I Also noted that this Temperature KVM had a Higher voltage reading that the normal KVM we would use to read the voltage from PS5 . Infact the normal Voltage KVM is half of the voltage read by the Temperature KVM. So I chose that one for a better signal to noise ratio. Is this the correct value. I'm not sure yet. but we will find out.

I ran this over night running multiple measurments. 


Another  Note: The PCAL Laser Chassis at End X has been showing a Red LED that is not normally red and Labeled "I limit" or "l limit" either way. The First time I saw it was right after a power outage so i thought it was just a weird one off sort of situation. I just powered the laser Off and back on again and the LED went away.
But I saw it had happened again yesterday, and power cycling the Chassis did NOT resolve it. I checked the MEDM screen and saw that  H1:CAL-PCALX_LASERDIODECURRENT was jumping around 9.7-10.0 Amps. So I simply changed the voltage a little and brought the voltage back up and it resolved the issue. l limit was no longer lit. Checking on it today and it seems to still be functioning normally now.

All spheres are now back in their Nominal configuartion.... bolted to the IFO.

HAM7 power budget repeat

Ryan S, Sheila

In summary, after removal of the A:L2 apperture stop we still see about 4% extra losses in HAM7.  We searched for the rejected beam from SFI1 in both directions with lights out, IR card, and viewer.  To explain a few % loss we should expect to have 10-20urad in this beam, which should be visible with lights out an a viewer.  We also noticed that the beam is off in yaw at the location where we had an iris after ZM1.  

Since Ryan and Camilla aligned the beam onto the SQZT7 PD yesterday, we are noting the power on that PD here after each measurement so we can use that to account for fluctuations in power out of the OPO.  

• out of OPO 1.354mW std 0.5uW PD 1.26-1.154 max-min, repeat in same location 1.340mW std 0.57uW PD: 1.26-1.154 max-min
• after ZM4: 1.209mW std 11.5uW  PD 1.233-1.12  
  • PD ratio: 98%  power dropped during measurement
  • power meter ratio:  89%(1st meas) or 90% (2nd meas)
• after BL1: 1.265 mW std 2uW  PD 1.241-1.14
• before BM1 (SFI1 return): 1.268 mW std 582nW  PD  1.23-1.11
• Remembered to start turning lights off
• before ZM1: 1.342 mW std 688nW  PD 1.24-1.11
• after AP1 before SF1 (on the way to FC): 1.316 mW std 680nW  PD 1.235- 1.08
• before BM1: 1.267 mW std 831nW
• on SQZT7: 1.191 mW std 5uW PD: 1.2032 much quieter with curtain up  (9.5% loss where we expect 4%)

From the control room, we dithered ZM2 + ZM3 and tried to reduce the fluctuations in the SQZT7 IR PD, we were able to recover a 4% of power this way, with fairly small adjustments (+9urad ZM2 P, +19 urad ZM2 yaw, 5 urad ZM3 yaw).  

One more round of power measurements: 

• out of OPO: 1.334 mW std 480nW  PD 1.248
• on SQZT7: 1.217 mW std 2.8uW (8.8% total loss)
• before BM1: 1.265 mW std 600nW  PD 1.25 (5% losses from 2 passes of SFI1)
• after BL1: 1.272 mW std 1.6uW  PD 1.25 (no loss from B:L2 apperture stop)
• after ZM1: 1.307 mw (not perfectly centered)  PD 1.25 (2% loss from 1 pass of SFI1)
• on SQZt7: 1.227 mW std 900nW  PD 1.25 (8% total loss)

 

New input alignment settings for IM1, IM2, and IM3

K. Kawabe, E. Capote, L. Dartez

This log covers work that started yesterday. We set out to scan the IM1 pointing to see if we could find evidence of clipping and to potentially identify a preferred input pointing configuration. We applied a dither to the IM1 and IM3 suspensions to use IM4_trans and the ISS second loop QPDs as sensors. This test was laborious because each new IM1 pointing mis-centered the beam on both QPDs. Keita pointed out that we can use IM2 and IM3 to center the beam on the IM4_trans and ISS second loop QPDs, respectively. Moreover, by centering the beam on IM4_trans and the ISS second loop QPDs, we get the beam for free on the POP QPDs (even though it is not centered there). To support the argument that we can arrive on a pointing now that will be relevant once we open the arms, we note that the QPD NSUM levels for the IM4_trans, ISS second loop, REFL WFS A and B QPDs are all consistent with what we had in O4 at 2W. The NSUM levels of the POP QPDs is consistent with what we had in O4 at 2W straight shot (PRC misaligned) as well. During this test we paid particular attention to avoid moving the input alignment to a spot that would have the RMs near their actuation range to keep the beam centered on the REFL QPDs.


For each IM1 pointing trial we did the following: 

1. Move IM1 alignment to new trial position
2. Walk the alignment of IM2 and IM3 to center the beam onto IM4_trans QPD and the ISS Second Loop QPD (within about 0.04 in PIT and YAW). I used IM2 to center the beam onto IM4_trans and IM3 to center it onto the ISS Second Loop QPD.
3. Check that the beam hasn't fallen off of the REFL PDs or the POP PDs and that the NSUM, PIT, and YAW signal values are at roughly the same values as they were before the IM1 adjustment.
4. Run the DC centering loops to center the beam on the REFL PDs and ensure that the RMs are not close to their actuation range. 
5. Measure the transfer function from the IM1 and IM3 DAMP banks to the IM4_trans and ISS second loop QPD SUM channels while injecting an 8Hz excitation into the IM1 and IM3 SUS TEST banks. 

The IM1 trials we tried are as follows:

Nominal position (the IM1 position when we began): 524.2 / -386.6 (P/Y)

Trial 1 (pink): (+30 uRad Yaw): 524.2 / -356.6 (P/Y)
Trial 2 (brown): (-50 uRad Yaw): 524.2 / -436.6 (P/Y)
Trial 3 (green): (-10 uRad Yaw): 524.2 / -396.6 (P/Y)
Trial 4 (blue): (+40 uRad PIT): 564.2 / -386.6 (P/Y)
Trial 5 (red): (-40 uRad  PIT): 484.2 / -386.6 (P/Y)

The five trials for this test were split across two days. And the excitation amplitude was not necessarily constant across all 5 measurements. This made it difficult to compare today's measurements against yesterday's. In any case, we think that the position at Trial 4 is the best one so far in that it shows the lowest coherence between the dither at IM1/IM3 and the IM4 trans QPD. We do not know or think it is unilaterally the best position, but we think it is better than it was before we started this. We won't know more until we have the arms. 

The new slider values for IM1, IM2, and IM3 are in IM_alignment_sliders.png. A screenshot of the TFs we took is at blueisgood.png. The colors of the traces correspond to the color next to each trial listed above. The blue trace has the best coherence for most of the measured transfer functions (and for all of the IM4_trans measurements). The DTT template we used can be found at ~keita.kawabe/IM1_moves_IM4_trans_ISS_QPD.xml.

Opening Cryotraps and Ion Pumps to Corner Volume

Per WP 13497

I opened IP1/2/3/4 to the corner volume at 18:38 UTC / 11:38 PDT

GV8 Soft closed  at 20:47 UTC / 13:47 PDT

GV7 opened at 21:20 UTC / 14:20 PDT

GV5 opened at 21:48 UTC / 14:48 PDT

Both GV5 & GV7 opened between 45-50 psi, and the holding pressure is set to 55 psi.

GV6 and GV8 will remain soft closed to isolate the beamtubes. CP1 and CP2 are now open to the corner volume to assist with the water pumping, water is still the dominant gas after ~22 days of pumping, see corner RGA scans in alog 91446

Corner pressure is decreasing as expected.

PR3 moved to O4 slider (not OSEM), next we need IM4 scan

I've moved PR3 back to latter half of O4 based on the slider, not OSEM.

Assuming that the ITMX angle is good and the beam deflection angle through the BS is the same as before, the plan to get ready for the arm peeking is as follows.

Find a good IM4 angle where the ITMX reflection comes back to ISCT1 camera (Louis is working on it).

Once that's found, align PRM, refine PRM and IM4 alignment to have a good PRX flash.

After that we might have to walk the beam on PR2 without touching ITMX and PR3. Unless there's a convenient script to do that, you'll move IM4 a bit, change PR2 so that ITMX retro reflects, and change PRM to recover PRX.

By iterating, you'll eventually settle on the beam position on PR2 that will give you an ok signal on LSC or ASC (hopefully both) POP sensors in HAM1. 

Also work on the ISCT1 alignment for the ALS beam, but this will be on Monday.

CER Kepco Power Supplies

WP13495

The following supplies were replaced in the CER Mezanine.

Kepco Power Supply in VDD-C6 Rack, Left Slot U31-29, ISC-R3&R5 +24V
Old S12001945
New S12001992

Kepco Power Supply in VDD-C6 Rack, Right Slot U31-29, ISC-R3&R5 -24V
Old S1201946
New S1201947

The negative supply was oscillating between 22V and 21V when measured before replacing, possibly due to failed fan.  New supplies were adjusted to +/-24V at the racks.

Caroline C, Marc P.

To the operators: What to do when JAC lost lock and JACK_LOCK cannot lock it because WFS went crazy.

This morning JAC lost lock due to temperature drift (temperature control was on) and at the same time WFS went crazy. After that JACK_LOCK guardian couldn't lock it, just kept scanning without success because the alignment was very much off.

When this happens, what you should do is:

• Move JAC_LOCK to DOWN.
• Open JAC_WFS_MASTER medm screen and clear history for DOF1_P and DOF1_Y.  JAC_WFS_crazy.png
• From that screen, open JM1 screen and you'll see that the LOCK_P and/or LOCK_Y output are big, like (JAC_WFS_crazy_JM1.png). Click "Lock Filters" and clear the history of P and Y.
• Move JAC_LOCK to LOCKED.

For the lockloss and WFS behavior see jac_lockloss.png.

 JAC lock voltage was drifting lower and lower, which meant that you must have cooled JAC down, but the temperature servo was heating it more. Ultimately we need a temperature servo to keep the lock PZT voltage constant rather than keeping the temperature sensed by the thermistor.

After the lock voltage alredy hit the bottom rail, it took about a minute for JAC to completely lose it. During this time, JAC_L error increased as the JAC slowly became off-resonant, and of course the same signal is seen by all WFS segments. Since WFS centering is not perfect, this increased WFS P and Y signal. JAC ASC tried to counter this by twisting JM1 and the PZT mirror without success.

Finally the WFS was turned off but mirrors were already heavily misaligned at that point. 

Corner RGA Scans - August 7 2026

RGA scans were collected for the corner volume using the new PrismaPro RGA. This RGA tree had been rebuilt and baked at high temp for 2+ weeks. Scan info below, raw data files will be posted to the DCC at T2600329.

RGA Model: Pfeiffer Prisma Pro

EM Voltage: 1200V

Dwell Time: 1s, 0-100 AMU, 10 pts/AMU

Valve States: GV5 & GV7 closed, FC2 & FC4 closed (Relay Tube removed & FCB-1 section common with corner)

Pumping: 3x 2000 l/s Turbo pumps, 1x 500 l/s turbopump (HAM6)

RGA filament has been on since 7/22 after RGA tree bakeout

Corner Pressure (8/7/26): 3.2E-7 Torr (PT120B)

Corner Pressure (7/27/26): 5.3E-7 Torr (PT120B)

Comparison plot showing partial pressure decrease after an additional ~10 days of pumping with turbo. Corner started high vacuum pumping on July 16th 2026 (22 days of pumping with turbopumps only)

DAQ CRC error trend over past 6 months

Dave, Erik, Claude

Claude AI wrote a python script to plot the H1 DAQ CRC rates for the past 6 months for all frontend and both DAQ legs (see attached). This plot only shows when an individual DAQ leg recorded a CRC error from the front end. The times there were CRCs on both legs were usually due to model restarts and not spontaneous errors, so these have been removed from the plot.

The vertial lines align with Tuesdays and possible maintenance activities.

General first thoughts are: over the long term the CRCs are fairly randomly distributed over front ends and DAQ legs; in the past week they have been concentrated on the 0leg and the two frontends iscey, seib1.

Friday Ops morning shift report.

TITLE: 08/07 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: CALM
    Wind: 3mph Gusts, 1mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.06 μm/s 
QUICK SUMMARY:

I came in this morning to a Vacuum Alarm on H0:VAC-EX_X2_PT524_PRESS_TORR. Wait! Dont panic! Vac Team had already put in an alog about it. 
Other than that Every thing looks good.... EXCEPT:  the RMS 1 & 2 are saturating for some reason. Tagging SUS
This started to happen at a round 7  UTC .  I took those Suspensions to Safe.

X-End Station PT524 CC Tripped

Found PT524B cold cathode gauge tripped/off, turned it back on, now we wait for it to comeback.  Gauge was tripped yesterday around 23:49 utc.

SQZ loss measurements

This alog was intended to be a comment on 91436

This morning we continued to use the crane that Camilla and Ryan devised to try to get more reliable power budgeting measurements on the VIP.  Our previous measurements with the power meter held in a hand and hovering over the table consistently showed that we have something like 4% extra losses in HAM7, but they have not been repeatable enough for us to track down the location of the losses.  The crane set up helps us set the angle of the beam profiler head by using a clamp on the post, and also gives us much more steady measurements of power, so we were able to make some progress in identifying the location of losses.  However, we think that the power out of the OPO was drifting by 1-2% during these measurements, which makes the measurements less reliable for finding losses.  

We do think that we have about 0..8% loss at B:L2, where the difficult to align apperture stop is.  This apperture stop catches a rejected beam from B:P1 which is scattered light from the interferometer, so we need to keep it.  We looked for space to move it off the lens mount onto it's own separate mount, but the platform is very crowded with bases and dog clamps in this area, so that would not be an easy solution.  

For the naming of optics see:  D2000021

• (location A) after SFI1 return (before BM1): 1.251mW. (readjusted crane and centering of beam on power meter)
• (same location as A) Moving FC1 and watching SFI1 Return power. Starting P 225, Y -156 (We do not see obvious evidence of clipping in SFI1 on the return path in this data).  
  • 205 Pitch  1.247mW, STD dev 0.59uW
  • 225urad Pitch   1.247mW, STD dev 0.51uW
  • 245urad Pitch   1.247mW, STD dev 0.88uW
  • -156urad Yaw 1.246mW, STD 0.66uW
  • -136urad Yaw 1.246mW, STD 0.57uW
  • -176urad Yaw 1.243mW, STD 0.54uW
  • Starting 1.246mW, STD 0.5uW
• (location B) between SFI1 polarizer and rotator (on way to FC): mean 1.315mW std: 0.41uW.  Comparing this to above numbers it implies we have a loss of 4.9%, 5.2%, or 3.4% using number below, where we expect 2%
  • We decided to measure here instead of right out of the OPO because we were concerned that the slight angle of the beam coming out of the OPO might have been making it hard for us to put the power meter head perpendicular to the beam, and it was easier to get the angle right in this location.  In the end we got similar powers and loss estimates measuring here as measuring right out of the OPO.
• (same location as A) after A:P1 : 1.269mW STD dev 1.4uW; unlocked reloacked OPO retook to be 1.270mW STDdev 2.3uW;  1.270mW STDdev 1.7uW. Implies loss of 3.5% where we expect 2%
• (location C) after B:L1: 1.260mW std 2.1uW  1.259mW std 1.5uW 1.258mW 1.8uW 1.260mW 1.2uW Implies 0.8% loss from B:L2, probably clipping on apperture stop.
• (repeat of location B) back to between SFI1 polarizer and rotator (on way to FC) 1.330mW std 0.66uW 1.329mW std 0.67uW 1.329mW std 0.46uW  Power must have drifted up 1% since our first measurement here.
• after SFI1 before A:L2 : 1.327mW std 0.91uW  1.328mW .66uW 1.326mW 0.80uW 1.324mW std 1.1uW This implies very low loss from SFI1's rotator and 2nd polarizer, although it is possible that the rejected beam from A:P2 could also be on the power meter in this location, we could not identify that beam on a card. If the apparent loss of about 1% from each pass of SFI1 is really from misrotation the rejected beams would contain about 10uW, which we could search for more thourughly with the lights off using an IR card with a viewer.  
• after A:M3 1.321mW std 0.37uW; 1.321mW std 0.52uW; 1.320mW std 0.6uW; 1.320mW std  0.5uW Implies 0.5% loss probably at the aperture stop attached to A:L2.  
• back to after SFI1 before A:L2: 1.305 std 0.7 1.305 mW std 0.7uW 1.316mW Power is drifting enough to make these measurements confusing. 

Access System - EY

The UPS for the EY Access system that powers the network switch a camera failed this afternoon. Power to the cameras and switch was bypassed for now.

DAS system, tap testing to calibrate distances along fiber

Jenne, Wanda, Shoshana, Gizem

We started very early this morning to beat the heat, and performed 'tap tests' at various points along the length of the arms to identify positions along the length of the fiber (according to DAS) with GPS positions (according to Wanda's phone).

Spreadsheet attachment is information about where along the fiber Shoshana and Gizem identified our tapping in the data, and associated time stamps.  I've also copied the spreadsheet data to a google sheet, so that we can add to it.  

We tried to do more dense taps on the 'inside of the vertex' side of the arms, where the fiber actually is.  This required some walking out in the sand along the arms, so we had sun hats and knee-high boots and plenty of water.   We also did a few taps along the road during our drive back, to get some more coarse information along the length of the arms.  At the Xend station, there were too many tumbleweeds for us to walk along the inside-vertex side of the arm, so there at EX we did our more dense taps along the road side, with the exception of the EX vault location. 

In the attached photos, you can see some examples of our tap test method.  Gerardo provided us with a scrap piece of steel that we used as a strike plate.  We also borrowed a sledgehammer from the mechanical / vacuum parts lab.  For most of the Yarm, we only did 3 heavy strikes and Gizem and Shoshana chose the strongest signal from that as our time.  Once we were on the road-side of Yarm, and then for all of Xarm, we added some light tapping that seems to have helped identify which distance bin (called a "channel" in DAS terminology) we were closest to.  The photos are also labeled with X/Yarm, and position number, which corresponds to the position numbers in the google sheet - I tried to capture features in the photo to help identify where exactly the strike plate was.

Wanda has added to the google sheet the GPS locations that she identified while we were at each tap point.

The last photo shows our used (but can be used again in the future!) strike plate. 

I have attached some screenshots which show what the referenced path looks like for the x-arm. Further, it demonstrates how the optical metres of the fibre are now referenced to a certain co-ordinate. With this, we can now correlate any events that we detect to a physical location. In this software, a straight line is drawn between two referenced points. 
In picture 1, the whole arm is shown. 
In picture 2, it is zoomed in on the area around the corner station, showing the limitations in our technique as it is relatively rough considering we know the fibre is curving at this point. 
In picture 3, we see how hovering over the waterfall plot will produce a red point in the refenced fibre showing the location of this channel. 

And here are some more pictures of the georeferencing.

Seal Replacement on GV6 Air Cylinder

Travis, Gerardo, Jordan

During the closing of GV6 back in May, we noticed that there was some blow-by in the pneumatic system when trying to hard close the valve, see alog 90093. 

We were able to hard close the valve eventually but as preventative maintenance we wanted to replace the air cylinder seals, similar to GV7.

Prior to disassembly we measured the locations of the reed switches from the top surface of the bottom plate to the bottom surface of the reed switches:

Bottom Switch: 1 1/8"

Top Switch: 49 1/4"

We then disassembled the air cylinder and replaced the seals following procedure/notes collected during the GV7 repair. During cleaning of the old grease on the piston head, we noticed there were two burrs on the top of the piston, we did not notice any damage to the inside of the cylinder, but as a precaution we used a small flat file to remove the burrs. We also chased the threads on the four threaded rods with a die to aid with reinstallation. After cleaning and inspection of the cylinder tube, we found no issues or damage so we decided to continue to use that cylinder and keep the new one as a spare.

No other issues encountered, we removed the old seals, cleaned the grooves, added copious amounts of the supplied grease to the o-rings, seals and the inside of the air cylinder, and then re-assembled the cylinder tube. Pictures posted below and a final procedure is in progress and will be posted to the DCC.

We did not get a chance to cycle the valve after the seal replacement, so we will continue tomorrow with cycling the valve.

 

BSC6 Annulus Ion Pump Work

(Jordan, Travis, Gerardo)
We removed and replaced the AIP for BSC6, no real complications while doing the work.  However the joint at the AIP and the isolation valve has a tiny gap towards the bottom, we started pumping down on the system and it appears to be a solid union, we will go and visit tomorrow and see how the pressure is doing.  On a side note we did find a flex metal hose that has a leak, it has been removed from circulation.