Displaying reports 1121-1140 of 88171.Go to page Start 53 54 55 56 57 58 59 60 61 End
Reports until 10:17, Tuesday 24 March 2026
H1 ISC (SUS)
oli.patane@LIGO.ORG - posted 10:17, Tuesday 24 March 2026 - last comment - 11:05, Friday 27 March 2026(89615)
BHSS / BHD work Mar 23: OMCB almost done, OMCA ready for alignment!

Elenna, Oli

Summary: OMCB has its DCPDs installed and most of its stoppers (barring one that needs to be retapped + helicoiled). OMCA has been aligned according to the OMCA / OMCB install template and is ready for laser alignment. Cabling for both OMCs should be good to go.

After last week's issue of the OMCB DCPD A (TRANS) missing a diode hole (89583), we were able to clear up the issue and fix it (89606). Elenna then installed the DCPD B (REFL) diode. Note that once again there were tiny metal shavings below where the DCPD's were installed, which we picked up with a qtip that we wet with iso. Once we had both installed (pic), we installed the rest of the stoppers around OMCB. The only one we didn't install is one of the vertical stops. This is because there was an issue with the helicoil last week, and we ended up having to remove it. We think this might be due to an issue with the threads, so we are waiting on a 3/8"-24 tap to retap the hole before installing a new helicoil. Because we don't have this stop yet, it doesn't really make sense to fasten on the butter dish, but we might just sit it on today to hinder dust accumulation.

We also realized that the PZT cables were going to be way too short to reach the cable pylons for both OMCA and OMCB, so we very carefully opened the peak cable wraps on the OMCs and took out what we think should be enough. On OMCB we noticed that the little copper wrap for one of the PZTs was not right above the PZT as it should be, but instead was on the other side of the peak cable wrap and was only wrapped loosly around one of the cables. Because of this we just removed the wrap. The cables right above the PZT are looking fine and don't look like they need anything to hold them together.

I had been confused about the OMCA / OMCB install template for the past few days, since installing it was putting OMCB further back in its slot than OMCA, but I was able to confirm yesterday in eDrawings that OMCB is actually supposed to be an extra 1 mm away from the front of its slot as compared to OMCA, so we moved OMCA into position and bolted it down.

I also went in and installed the magnet mounts for the OSEM magnets (without the magnets), as well as the big mass on the back of the BHSS.

 

Installed serial numbers:

OMCB (SN 105)

Images attached to this report
Comments related to this report
corey.gray@LIGO.ORG - 08:46, Thursday 26 March 2026 (89652)EPO

Tagging For EPO photos.

elenna.capote@LIGO.ORG - 11:05, Friday 27 March 2026 (89671)

The naming convention listed above is incorrect. Please refer to alog 89669 for correct information.

H1 TCS
camilla.compton@LIGO.ORG - posted 09:20, Tuesday 24 March 2026 (89616)
CO2Y Tripped off, back on now.

Yesterday during the cleanroom move, CO2Y tripped off, this is a known issue when people get near the TCS racks, FRS 6639. I turned it back on this morning by pressing the "GATE" button on the chassis. 

H1 CDS
david.barker@LIGO.ORG - posted 08:38, Tuesday 24 March 2026 - last comment - 13:21, Tuesday 24 March 2026(89613)
Recovering SWWD and HWWD trips after Mon 21:45 PDT earthquake

Corey, Fil, Erik, Jonathan, Dave:

Last night's earthquake caused SWWD trips for ETMY, ITMY, ITMX. It also caused a HWWD trip of ITMY (BSC1) which was concerning.

We were able to untrip the SWWDs, but we kept ITMY DACKILLED while we work on its HWWD.

Jonathan went into the CER and pressed the RESET button on the ITMY HWWD chassis, this did not untrip the power to the ISI coil drivers. We tried a second time, again no restoration of power.

The front panel and the readback by h1susitmy both agree that the only red led is SEI-trip, the input conditions PD=osem-photodiode-rms and LED=osem-led-current are both GOOD, which should have permitted the reset.

But when the reset button was pressed, the PD led went RED and the unit did not reset the SEI trip.

Fil is heading out to reboot the unit and possibly replace with a spare if it is not working correcty.

Images attached to this report
Comments related to this report
david.barker@LIGO.ORG - 13:21, Tuesday 24 March 2026 (89624)

WP13115 to possibly prevent future HWWD trips by shortening time-to-trip of SWWD to 15 minutes.

david.barker@LIGO.ORG - 10:25, Tuesday 24 March 2026 (89618)

Fil got the ITMY HWWD to fully reset by keeping the "fault reset" button pressed for many seconds.

david.barker@LIGO.ORG - 13:14, Tuesday 24 March 2026 (89622)

Attached plot shows the suspension started recovery when the SWWD SUS tripped at 22:19:52 and 41 seconds later the HWWD tripped at 22:20:33

Images attached to this comment
david.barker@LIGO.ORG - 13:17, Tuesday 24 March 2026 (89623)

Summary of our 3 HWWD trips has been submitted to the DCC T2600092

As was done at the end station test masses, we need to reduce the time-to-trip for the SUS SWWD from 20 minutes to 15 minutes.

LHO General
corey.gray@LIGO.ORG - posted 07:52, Tuesday 24 March 2026 - last comment - 08:49, Tuesday 24 March 2026(89611)
Tues DAY Ops Transition: Maintenance Day

TITLE: 03/24 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: 14mph Gusts, 10mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.19 μm/s 
QUICK SUMMARY:

Arrived to see lots of tripped Watchdogs.  This was due to a M7.5 Tonga earthquake from last night just before 10pm local time (5utc).  Dave contacted me to give me the heads up on this and noted that ITMy actually had the Hardware Watchdog trip---this requires someone to go out to the CER to push a button to restore coil drivers.  We were hesitant on addressing this without Jim's guidance--not sure how powering things back on would affect the system.  Will message Jim with a heads up for BSC1's ITMy/BSC1-ISI/BSC1-HEPI.  Will continue bringing everything else back.

Other than that, today is Maintenance Day.  The Filter Cavity Tube has light flashing and so its small gate valves must still be open (I had thought the discussion was to close these gate valves to allow craning over the FC Tube, but not certain on this.

Day1 of 2-day CEBEX workshop begins today.

Comments related to this report
corey.gray@LIGO.ORG - 08:49, Tuesday 24 March 2026 (89614)CDS, SEI, SUS

Earthquake Recovery Status:

ITMy Hardware Watchdog continues to be looked at with Fil/Jonathan

UPDATE:  Fil was able to restore the ITMy watchdog (he held the RESET for a few seconds and waited for the lights to change on the front panel).  ITMy HEPI/ISI are redamping/isolating.

  • HAMs restored:  HAM1/2/3/4/5/7/8
  • BSCs restored:  ETMy/BS/ITMy/ETMx/ITMx
    • HEPIs restored:  ETMy/ITMy/ITMx
  • Software Watchdogs restored: 
    • ETMy:  SUS & SEI
    • ITMy:  SUS & SEI
    • ITMx:  SUS & SEI
  • Hardware Watchdog tripped:  ITMy (just got restored by Fil)
H1 CDS
erik.vonreis@LIGO.ORG - posted 07:23, Tuesday 24 March 2026 (89610)
Workstations updated

Workstations updated and rebooted.

H1 SQZ
camilla.compton@LIGO.ORG - posted 16:58, Monday 23 March 2026 (89607)
FC alignment improved with help of PSAMs, still not well aligned to SQZT7/IFO and FC simultaneously

Sheila, Sophie, Camilla 

The HAM7 PSAMS (ZM2,4,5) were railed last week, we noticed that the ZM2 alignment changed Friday after the FC gatevalue was closed which led us to noticing this. Reset the ZM4 and ZM5 PSAMS, following 84639 and adjusted sliders to bring osem values back. ZM2 was not railed, something on Friday afternoon (maybe the GV being closed) stopped ZM2 PSAMS being railed.

Once the FC GV was opened, we could see a beam on FC-IR camera. We went to the FCES and after mis-aligning FC1 and FC2 while moving ZM3 would could see a green beam on the green camera. After temporarily tuning up the exposure and adjusting FC1 and FC2 we could see beams on both IR and green cameras and the best flashes we've had so far, 20 on FC_TRANS_C (green) with 6.5mW in and 1.35 on FC_TRANS_D (red) with 75mW SEED. Sheila adjusted the IR camera steering mirror in Pitch as she had last week to bring the beam more central on the camera. 

Looking back to November, typical flashes when we have the OPO locked and FC aligned with 7.8mW into FC green are 60 on FC_TRANS_C (green), 0.8 on FC_TRANS_D (red) and 0.002 on OPO_IR_PD, see attached

Images attached to this report
H1 CDS
david.barker@LIGO.ORG - posted 16:50, Monday 23 March 2026 (89608)
h0vely IOC dropouts from network

During the Y-manifold vacuum work today we have had three occasions where the control room and EDC had lost connection to h0vely IOC for several seconds. The times are: 11:02, 14:39 and 16:26 PDT.

LHO General
corey.gray@LIGO.ORG - posted 16:34, Monday 23 March 2026 (89590)
Mon Day Ops Summary

TITLE: 03/23 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 activities & new visitors on site today.  Main activities were the VAC team working on swapping a pneumatic actuator for GV7, squeezer alignment checks (cont.), SPI & BHD work in the optics lab.  (Also had Girl Scout cookies arrive!)

LOG:

H1 SQZ
sheila.dwyer@LIGO.ORG - posted 13:37, Monday 23 March 2026 (89596)
Friday's filter cavity alignment work

Sheila, Tony

On Friday we continued trying to get flashes in the filter cavity for 1064nm, 532nm, and IR light onto the SQZT7 diode which we are using to establish that we are going through the VIP without clipping.  

At the start of the day we saw IR flashes of at max 0.04 counts on SQZ-FC_TRANS_D_LF with the OPO locked with CLF (with 21mW on CLF trig PD) 1.7 counts on FC_TRANS_C_LF with 5mW into the green fiber, and 36e-6 counts on OPO IR PD.  We saw that the green was clearly misaligned in yaw in the filter cavity, and we were able to improve the IR flashes and IR on SQZT7 with some yaw moves, but that made the green flashes nearly disappear.  We pio'd MOTOR 3 (H:M2) -710 counts, which improved the green flashes to 6 counts.  

Then we could see that the IR flashes and on SQZT7 were easiesr to improve with pitch moves, and that we no longer loose the green by improving them, so we spent some time trying to walk ZM1/2/3 for slow improvements, to get IR flashes of 0.1 counts, 83e-6 on SQZT7, and green flashes of 5.  (22:30 UTC March 20th)

This was slow going, so we decided to go back to FCES with cameras to see if we could get some photos or see flashes.  We will continue from the FCES this afternoon. 

H1 PEM (PEM)
corey.gray@LIGO.ORG - posted 13:06, Monday 23 March 2026 - last comment - 10:11, Tuesday 24 March 2026(89605)
3-month Trend of Dust Counts At BSC2

Betsy wanted a look at the last few months of dust trends for BSC2.

(This is Dust Monitor LVEA10 which was moved to BSC2 in Feb [alog89137].)

Images attached to this report
Comments related to this report
betsy.weaver@LIGO.ORG - 10:11, Tuesday 24 March 2026 (89617)
Calum and I looked over this plot - the counts are not too bad during the many periods of nearby craning and other activity.  The platform and dome have not yet been cleaned.  I confirmed that the cross flow tent has positive pressure so Calum and I are comfortable with this new "cleanroom" configuration.
H1 General
jennifer.wright@LIGO.ORG - posted 12:48, Monday 23 March 2026 (89604)
Cleaned out contamination control flashlight array

One of the flashlight arrays we used during the vent had a bunch of battery corrosion in each battery compartment.

I used isoprop and water on long q tips to clean these out in the optics lab. It is now drying on the bench next to the fume hood. See first pic.

Unfortunately I didn't realise the sink hadn't been used in while and turning this on splashed water on some nearvby electtronics, second pic.

The pipes attached to the taps also leak.

I dried off the silver box and the extension block after powering off the extrension block, it was just some water spraying on it so should be fine.

 

Images attached to this report
H1 CDS
david.barker@LIGO.ORG - posted 12:24, Monday 23 March 2026 (89603)
CDS Overview Shows Timing Card Firmware Version

Erik, Marc, Dave:

I've updated the CDS Overview to show the timing card firmware as a color block in the RGC version section of the IOP model.

For each IOP model, the top part of this block shows the RCG version, GREEN=5.5, BLUE=5.5.2. The lower part shows the Timing Card version, GREY=old, DARK-BLUE=new.

For user models this block just shows the RCG version as before.

Images attached to this report
H1 PSL
ryan.short@LIGO.ORG - posted 12:04, Monday 23 March 2026 (89602)
PSL 10-Day Trends

FAMIS 31130

Not much to report this week. Noisy FSS TPD times line up with the IMC naturally flashing through resonance, and looks like there were some temperature spikes for a few days last week, but these appear to have stopped.

Images attached to this report
H1 SEI (SEI)
anthony.sanchez@LIGO.ORG - posted 11:17, Monday 23 March 2026 - last comment - 16:40, Wednesday 25 March 2026(89599)
Hepi Pump Trends (Monthly)

Hepi Pump Trends (Monthly) Famis 39954:
 

On Jan 26th the HPI-PUMP_EX_PRESS1_PSI started rising in maximum pressure. and on  maybe feb 2nd it started getting worse. Seems like it has plateau-ed on Feb 16th, but the Pressure still remains elevated.

That channel back in Oct was between 92.4-92.6 PSI. 
And now it's between 91.9 - 93.5 PSI. I'm not sure if this is out of bounds for HEPI.

Images attached to this report
Comments related to this report
jim.warner@LIGO.ORG - 16:35, Wednesday 25 March 2026 (89646)

I have looked at the EX pressures a bit and I suspect that one of the pressure sensors on the EX manifold has gone bad.

On the attached trend, the top 2 traces are PRESS1 and PRESS2, bottom 2 traces are the same pressures at EY. EX PRESS1 starts seeing bigger peak to peak signal starting about 50 days ago, but PRESS2 doesn't see this increase in pressure noise. Second attach image is a zoomed in trend of the same channels. EX PRESS1 seems to have some kind of 1hz oscillation. PRESS2 might be seeing some of this same signal, but not to the same extent. The supply pressure to the VEA at EX definitely doesn't see this 1hz signal, so I think it's either not real or it's being filtered out at the manifold.

I have yet to go down to EX and test this, but I will try to do so this week.

Images attached to this comment
jim.warner@LIGO.ORG - 16:40, Wednesday 25 March 2026 (89647)

FRS ticket: https://services1.ligo-la.caltech.edu/FRS/show_bug.cgi?id=37356

H1 AOS
sophie.muusse@LIGO.ORG - posted 10:46, Monday 23 March 2026 (89598)
CHETA Updates

X-Arm electronics:

All chassis have been tested mounted in the rack. All that is left is to replace the variable power supplies currently being used for the visible laser, fan and flipper with 5V, 12V and 15V DIN mounted power supplies respectively. 

X-Arm beam profiling:

X-arm is not behaving as predicted by the model especially in the horizontal axis.
The beam was profiled using the nano scan along a 55cm length after the second lens and a q-parameter was fit using this data. 
This is compared to the model and a Jammt model using the measured QCL q and assuming a linear optical system with the lens at the same distances as in the physical set up.
For the fit q-parameter the w at the ITM was found by propagating the q at L2 to the ITM.

Additionally, during the trouble shooting process a wedge was found on the first telescope lens (L1) which isnt in the optical system and was compensating for some of the astigmatism of the QCL. The effect of this is that in the data below the beam size at the ITM is too large and astigmatic. 
Discussion and solutions of this effect will be the subject of its own log.

Vertical

Measurement/model w0 [ µm] z [mm] w at ITM [mm]
Fit from data

978.9±22.7

 -1063.1±33.8

50.09
Fintrace

857.11

-500.64 61.38
Jammt 874.53 -572 62.1

Horizontal

Measurement/model w0 [ µm] z [mm] w at ITM [mm]
Fit from data 1280.3+/-54.9

 -1813.3±83.5

38.01
Fintrace

979.42

-653.71 54.38
Jammt 1013 -256 53.1

None of the values agree within the measurement uncertainty bounds, especially in the horizontal direction. We are also observing non-gaussian beam profiles on the nano-scan, plots attached, but this is predominately in the vertical direction. This structure isnt new and appeared when matt and I were initially profiling the lens and were able to see good agreement.
The fintrace and Jammt are close but not identical which would be expected as the Jammt does not include any additional optics outside the QCL and L1 and L2. We are currently working on determining the source of this discrepancy. 

 

 

Images attached to this report
H1 ISC (SUS)
elenna.capote@LIGO.ORG - posted 16:47, Friday 20 March 2026 - last comment - 13:48, Monday 23 March 2026(89583)
OMC build update for BHSS

This is a belated report of work done by me, Oli and Keita on the OMC builds for the BHSS, done yesterday March 19.

Exciting summary: build for OMCA is complete, including DCPDs and butter dish. OMCA is installed onto the BHSS platform and ready for beam alignment!

Less exciting summary: build for OMCB is halted as tombstone for DPCD A (transmission) is missing a required PCB hole for the electronic connection.

OMCA build notes:

OMCB build notes:

Images attached to this report
Comments related to this report
arnaud.pele@LIGO.ORG - 11:25, Monday 23 March 2026 (89600)

[Elenna, Camille, Arnaud]

We had a quick zoom meeting to discuss this issue. Relevant drawing is https://dcc.ligo.org/D1201273

It is likely that the backshell+PCB assembly was assembled flipped 180 degrees (items 4,5,6 on the drawing). To fix, remove the two 2-56 screws (item 14), flip the assembly and reattach it to the housing. Camille suggest slightly pressing down on the housing while removing those screws to avoid torquing the base with the bond.

corey.gray@LIGO.ORG - 11:30, Monday 23 March 2026 (89601)EPO

Tagging for EPO.

elenna.capote@LIGO.ORG - 13:48, Monday 23 March 2026 (89606)

After consultation with Arnaud and Camille, Oli and I were able to correct the problem with the PCB assembly.

On the call with Camille and Arnaud, we referred to the diagram in D1201273 and determined that part #4 is rotated 180. I could also see from this diagram that part #5 is rotated, since there was no notch visible at the top. So, for future installation, make sure the notch in part #5 is oriented upwards! This indicated to us that all that needed to happen was to unscrew the #14 screws, flip the assembly, and screw it back in (we had some concern that we might have to take apart the "sandwich" of parts between #5 and #4).

Indeed, that's all that needed to happen. I carefully unscrewed the screws on the back, flipped the assembly, and screwed it back in. I was then able to install the DCPD. We can now see the notch along the top!

Images attached to this comment
elenna.capote@LIGO.ORG - 09:56, Monday 23 March 2026 (89595)

I went back into the lab today to try to get a better photo of the problem. I wasn't able to, but I did get an ok photo of the other tombstone (on reflection of the BS) which has the correct three holes. It's hard to see, but you can use it as a reference to compare with the photo I have attached to the original post which is missing a hole. I tried looking from many angles, and I don't see even a hint of the third hole, which is evidence in support of Keita's theory that the electronics assembly is flipped 180 degrees.

Images attached to this comment
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