I have recently reported that the “mystery” beam on the spool piece wall near HAM3 was coming from the direction of ITMX (82252). To further this investigation, I started photographing the area around the ITMs and BS as best I coluld through our viewports (there is not a good view towards HAM3).  I found several unexpected distributions of light in the vertex:

1. 20 degree conical annular beams from ITMs

Both ITMX/CPX (Figure 1) and ITMY/CPY (Figure 3) cast an expanding annular “beam” towards the BS with a cone half angle of roughly 20 degrees from the main beam. My best guess is that it is produced by arm cavity light hitting the bevel of the ITMs (see cartoon in Figure 1). A good test of this would be to install the new test mass cage baffles at one or more of the ITMs at LLO (presuming Anamaria finds this beam at LLO) this upcoming break. The baffle should hide the bevel and eliminate the ring of light.

2. 45 degree conical annular beams from BS

The BS appears to cast an expanding annular “beam” with a cone half angle of 45 degrees, centered around the -X, -Y direction (Figure 2), and likely another annular beam, also with a half angle of 45 degrees, centered around  the  -X, +Y direction (evidence in Figure 3). I tried to find a geometry where the bevels were also the source of these beams but didn’t. My best guess is that the annular cone is produced by reflections of light from PR3 and the ITMs off of the inner surface of the circular cage around the BS, or the inside surface of the circular barrel of the BS itself (see drawings on third page of Figure 2). 

3. Reflection of BS in ITM elliptical baffles likely visible at ITMY and HAM3

The BS beam spot is reflected towards ITMY by the slanted piece of the ITMX elliptical baffle (Figure 3). While the actual beam is not reflected towards ITMY (it isn’t clipped), the baffle reflects light towards ITMY that is scattered out of the main beam by only a few degrees.

FLlamas - Tuesday, 2025-02-25

Start of report

Moved the Pcal upper beam at END-X to test for repeatability of the results seen on LHO:78373.

Recap:
As seen on first figure (chi_klm), the red squares highlight the inconsistency when moving the upper and the lower beam to the same direction (left aperture on target - fourth and fifth figures show the target) on the ETM. The other moves are consistent between upper and lower beam. Additionally, the second (2024_06_11_transition_upper_center2left_rawpcals_out) and third (2024_06_18_transition_upper_left2center_rawpcals_out) figure show the Pcal channels during the upper beam moving from the target center aperture to the left aperture and back. The blue color is for the PD values before making an actuation, the orange is for the values after the actuation, the title tells the actuation direction on the target and the x-axis is the time needed to average 10 hours within lock for each state (10 hrs before and 10 hrs after). From these plots we see that, during the upper-beam actuation to the left and back, the END-X Tx sensor - middle-left plot - decreased by 8 HOPs and 6 HOPs, affecting chi_XY. The END-X Rx value - top-left plot - dropping by 20 HOPs suggests additional losses of the beam downstream from the Tx sensor, potentially from clipping, but it is hard to see with the Tx changing simultaneously. There was an initial concern at the time of moving the upper beam that the actuations to the right aperture were the inconsistent ones, but after moving the lower beam we can have more confidence on the values corresponding to an actuation to the right aperture and raise concern on the actuations done to the left aperture.

Today:
Went to END-X to move the upper Pcal beam by actuating on yaw of the last folding mirror before the vacuum window (aka: the "inner beam" folding mirror.) The objective is to maximize the signal measured by the Rx PD when the target is in place. This is done by blocking the beam that will not be used and monitor the actuated beam with a voltmeter reading from "RX PD Mon" from the Pcal interface chassis (D1400153). The table below documents each relevant step from the procedure and the voltage used to assess such step.

The increase in signal after the actuation could be from clipping on the center aperture. An extra step between 3 and 4 where the beam is "optimized" on the center aperture would reveal if there is such clipping. The previous alog from a Pcal upper-beam actuation to the left agrees that this location increases the Voltage signal from RX PD Mon but the data shows 20 Hops of clipping... odd.

Nominal plan is to get a few hours of lock to assess the results from this actuation, and return the beam to it's nominal "center" state on the following maintenance Tuesday.

End of report

original post: SEI 2513

I restored the MSO (Missoula, Montana) picket to the picket fence. Hopefully it will increase the reliability of the picket fence for the few earthquakes that come from the northeast.

Turns out they changed the sensor to a different data rate and it hadn't been mentioned in the data aggregator.

Please SVN up at the picket fence folder if you would like to get this change.

TITLE: 02/26 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Wind
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 29mph Gusts, 17mph 3min avg
    Primary useism: 0.12 μm/s
    Secondary useism: 0.57 μm/s
QUICK SUMMARY:

• We're holding down as the wind is too high for locking
  • Windy.com forecasts the winds dying down this evening, around 7/8pm
• We're also shaking from an EQ from Indonesia
• 2ndary microseism is high but is going down

TITLE: 02/26 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Wind
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY:

IFO is in ENVIRONMENT due to high winds (attached screenshot) as well as a 6.1 EQ that just passed.

We are attempting locking since ALS is somehow able to lock and stay locked for over a minute, though DOFs are understandably having a hard time converging. The plan is to finish initial alignment and then go into OBSERVING. Winds are forecast to wind down starting 5PM PST.

Tuesday Maintenance was pretty calm - below is a summary of the work done.

Tuesday Maintenance Tasks (Trello, Work Permits and alogs)

• LN2 Fill (VAC) - DONE - alog 83037
• Tumbleweed Cleanup (FAC) - DONE - Work Permit 1226 
• EY Compressor Replacement (FAC/VAC) - DONE - Work Permit 12340
• Fire Pump Churn Test (FAC) - DONE - Work Permit 12346
• Termite Extermination (FAC) - DONE - Work Permit 12344 - (ex) Terminator “will be back”. Important Message: There should be very limited activity near the fume hood for the next week.
• Diesel Fuel Delivery (FAC) - DONE - Work Permit 12348
• Vent Planning Walk (DetEng) - DONE
• ForkLift Transport (FAC) - DONE - Work Permit 12316
• Temp Sensor Troubleshoot (EE) - DONE - Work Permit 12332 
• Camera System Test (CDS) - DONE - Work Permit 12345 - alog 83040, alog 83043
• Add new H1digi4 channels (EPICS and IOC) (CDS) - DONE - Work Permit 12352, Work Permit 12353 - alog 83038
• NoMachine Update (CDS) - DONE (pre-maint.). - Work Permit 12343 - alog 83040
• X6,Y6 VACSTAT Channel glitch detection implementation (CDS) - DONE -  Work Permit 12347 - alog 83040
• FSS Alignment Tweak (PSL) - DONE - Work Permit 12349 
• SQZT7 Work (SQZ) - DONE - Work Permit 12335 - alog 83039
• EX Beam Profile Measurements (ALS + HWS) - NOT DONE - Delayed to future Tuesday - Work Permit 12322
• EX Pcal Work (PCAL) - Requires Transition to Laser Hazard - DONE - Work Permit 12278 
• CP1 Controls Change (Dave/CDS) - DONE - Work Permit 12284 - alog 83037

Other:

• Jason did some PMC computer work and reports that the PMC power is a bit high and may need rotation stage calibration - if PSL looks weird, may be why. Alog 83035
• DAQ Restart from 1:00 to ~1:20 PST.
• LVEA and CER Wi-Fi are not working. CDS is investigating.
• Important Message from Termite Exterminators: There should be very limited activity near the fume hood for the next week.
• The X-Arm is no longer passable due to tumbleweeds.
• LVEA was swept by Ryan C - Alog 83041

LOG:

Sheila, Matt, Camilla

We aligned and took some SQZ HD data this morning but realized that the ZM optics were noisy with HAM7 tripped and the increased (60mph!! wind). After un-tripping HAM7, Matt and Sheila rechecked balancing and visibility, started at 98.3% but noisy, improved to 99.0%. Since then HAM7 tripped and was un-tripped again but assumed nothing would have changed.

NLG Measurements:

Data saved to camilla.compton/Documents/sqz/templates/dtt/20250225_GOOD_HD.xml

FC2 is misaligned during this dataset.

Under WP 12345 we continued the work we did yesterday.  Today Patrick got a change to the camera server running which allows us to set the maximum frame rate for the cameras.  This then gives us the ability to limit the amount of CPU/network resources we are using on the server (and also the clients).  We have currently limited MC1, MC3, PRM, PR3 to 25 fps.  This gives us a nice data rate that doesn't overload our camera heavy wall displays.  We will leave this code running for a while as a test.

Seeing the increase in PMC Refl variation after our small PMC alignment tweak last week, I took a look at PMC things this morning.  Chiefly, I slightly tweaked PMC alignment to see if I could change the variation seen in PMC Refl, and then revisited the amplifier pump diode injection currents after our previous measurement of the pump diode slopes.

PMC Beam Alignment Tweak

I first tweaked the beam alignment to the PMC using our pico mounts.  With the ISS OFF PMC Refl was hovering around 23.6 W, and after a couple of small tweaks PMC Refl was hovering around 23.4 W; this was the lowest I could get PMC Refl.  PMC Trans increased by roughly the same amount; it began hovering around 104.9 W and ended hovering around 105.1 W.  Not a large improvement, but also not unexpected.  I turned the ISS back ON and let things sit and collect data for 15 minutes or so, then took a look at the variation in PMC Refl before and after the tweak.  Before today's tweak PMC Refl was moving roughly 0.45 W peak-to-peak, and after it was moving roughly 0.27 W peak-to-peak.  This is closer to the variation before last week's alignment tweak so I left the alignment here.  Will check in on this later to see if it holds.

Amplifier Pump Diodes

That done, I took a look at the injection current for the amplifier pump diodes.  From our diode slope measurements a couple of weeks ago the pump diodes are outputting more power than they were at install.  Case in point, at install we were seeing ~68 W out of Amp1 with 9.0 A of injection current to all 4 pump diodes; now with 9.0 A for diodes 1 and 2 and 8.8 A for diodes 3 and 4 we have ~71.5 W out of Amp1.  Keep in mind, the pump diodes are powered in groups of 2.  So for Amp1, power supply 1 supplies pump diodes 1 and 2 and power supply 2 supplies pump diodes 3 and 4 (power supply 3 supplies Amp2 diodes 1 and 2, and power supply 4 supplies Amp2 diodes 3 and 4); this means that whenever we change the current of one power supply we are changing the injection current for 2 pump diodes.

Amp1 first.  Looking at the slope measurements, to get close to our pump diode output powers at install the injection currents need to be set at 8.7 A for all 4 diodes.  To see how this affects our PMC Trans/Refl relation, I turned OFF the ISS again and set the Amp1 injection current to 8.7 A for both power supplies.  This dropped Amp1 output to ~69.2 W (from ~71.5 W), Amp2 output to ~138.3 W (from ~141.0 W).  PMC Refl dropped to ~22.8 W and PMC Trans dropped to ~104.0 W (from ~23.5 W and ~105.2 W, respectively).  PMC Refl remained ~22% of PMC Trans after this change (21.8% vs 22.3%), so this implies a straight power drop with no real change in the beam quality.  Since this is as close to the install output power as I can get, I recalibrated the pump diode power monitors for Amp1 at this point, as based on the slope measurements we're clearly not outputting between 85% and 95% of our install output power (which is what the Amp1 pump diode monitors read at this injection current).  I set both Amp1 power supplies to 8.8 A as this gave a good balance of output power, PMC Trans/Refl ratio, and pump diode output power.  At this point Amp1 was outputting ~70.2 W, Amp2 was outputting ~140.1 W, PMC Refl was ~23.1 W, and PMC Trans was ~104.7 W.

Next I took a look at Amp2.  We had tested putting Amp2 back to its install injection current (8.6 A) when we recovered the PMC after the pump diode slope measurements and this was not great for the PMC; Refl increased and Trans decreased by large amounts.  So even though Amp1 is happy with similar pump diode power vs install, Amp2 seems to want more.  Now this was putting the Amp2 injection current back to the install level, but not looking at the actual pump diode output power.  To get close to the Amp2 pump diode output powers at install the injection current would have to be lowered even more (8.3 A for diodes 1 and 2 and 8.4 A for diodes 3 and 4).  The table below summarizes the results I saw when changing the injection current for Amp2; I've bolded the row that represents the closest I can get to our install pump diode output powers, based on our diode slope measurements from a couple weeks ago.

First things first, we are currently overpumping Amp2, as seen by the behavior of Amp2 output with the changes in injection current.  However, as the injection current of Amp2 is decreased the PMC gets less and less happy, with the transmitted power dropping quickly despite there being little change in the power output from Amp2, and a slight increase in injection current reduces PMC Refl while keeping Amp2 output the same.  I can think of 2 reasons for this off the top of my head: these lower pump powers result in more power in higher order modes vs the fundamental mode, or our Amp2-to-PMC mode matching is somewhat less than ideal when the amplifier is not overpumped (I'm leaning towards the latter, we've suspected for a while that PMC mode matching isn't ideal).  To test this we would have to take beam propagation measurements on the beam at these different injection current levels.  IFF there is enough time during the upcoming break in O4 (we would probably need 2 or 3 days, likely after the vent work) we want to revisit PMC mode matching, so we would take a look at this then.  I also want to note that at the install pump diode output power (bolded row), Amp2 output was very noisy, varying by roughly +/-1.5 W.

I also tried 9.3 A injection current on all 4 pump diodes, but this yielded very little improvement over 9.2 A (~0.2 W better for both PMC Trans and Refl).  Despite slightly overpumping Amp2, I left the Amp2 injection currents at 9.2 A as the PMC is performing better at this current setting; we will revisit this if/when we take a look at PMC mode matching.  I then recalibrated the Amp2 pump diode monitors to more accurately reflect the amount of power they are outputting now vs install.  Before and after pictures of the pump diode monitor calibration factors are attached (looking at the PumpPD column).

To end, I turned on the ISS and adjusted the RefSignal to -2.0 V so it was diffracting ~4% (RefSignal adjustment necessary since PMC Trans increased by ~1.5 W); at 12:30 PST, when I finished, PMC Refl was ~22.3 W and PMC Trans was ~106.4 W.

The LVEA has been swept, the only thing of note was that the west bay crane was not in its' parking spot, it was against the wall. Tyler was notified and is going to move it.

WP12343 opslogin0 upgrade

Erik, Jonathan:

Opslogin0 OS was upgraded from deb11 to deb12. Its nomachine server version was upgraded to 8.16.1 (which enabled the OS upgrade).

WP12284 CP1 stop fill on temperature drop

Janos, Dave:

A new version of cp_overfill_ioc.py was ran today which stopped the fill when the thermocouples recorded a drop in temperature of greater than 60C in 30S. The new IOC has additional channels, which were added to H1EPICS_CP1.ini. A EDC+DAQ restart was required.

WP12352 Update DAQ to recent camera move

Patrick, Jonathan, Dave:

Last week cameras 11-14 (MC1, MC3, PRM, PR3) were moved from hdigivideo1 (old server code) to h1digivideo4 (new server code). This new code has a lot more EPICS channels per camera, and two channels have been removed (_XY, _AUTO). So the the past week these cameras have been missing some of their channels in the DAQ, and I had to run a dummy IOC on opslogin0 to "green up" the EDC for the missing XY,AUTO channels.

Today a new H1EPICS_DIGVIDEO.ini was created to bring the EDC up to date. A EDC+DAQ restart was required.

WP12347 Add new VACSTAT channels to DAQ

Dave:

Following the addition of the X6,Y6 gauges to vacstat yesterday, these were added the H1EPICS_VACSTAT.ini for inclusion to the DAQ. A EDC+DAQ restart was required.

DAQ Restart

Jonathan, Dave:

The DAQ was restarted for new EDC ini files (H1EPICS_[CP1, DIGVIDEO, VACSTAT, CDSMON].ini

The new EDC restart procedure was followed. The only issue was a sponteneous restart of FW1 as it was writing its first full frame.

Procedure:

• backup old H1EDC.ini, generate H1EDC.ini
• check for channels duplicates (there were none)
• for each new channel, check it exists using caget (they all do)
• when idle, stop TW0 and TW1
• restart h1edc (the rts-edc_h1edc.service on h1susauxb123). At this point the only disconnected channels are TW[0,1] (they were)
• restart the DAQ 0-leg, this starts TW0. Wait for FW0 to write frames. EDC is only disconnected from TW1 at this point (it was)
• restart the DAQ 1-leg, this start TW1

Jonathan, Dave:

We added h1digivideo4's CDS Load Mon EPICS channels to the CDS Host Stats MEDM. A reminder that this MEDM can be launched by pressing the "COMPUTERS" button in the lower right corner of the CDS Overview MEDM.

Tue Feb 25 10:17:54 2025 INFO: Fill completed in 17min 49secs

Today was the first run of the new code, which terminates the fill on rate of thermocouple temperature drop rather than dropping below a set limit. This will free us from having to manage the limit during seasonal changes.

TCmins[-144C, -140C] OAT (+11C, 51F).

For now the plot still shows the old -90C trip level. I'm working on a new plot which shows the rate-of-change channels.

I'll make a detailed alog about the new code with its associated MEDM, striptools and plots in the next few days.

FAMIS26032

The script reported high noise for ITMX ST1 V1, ETMY ST2 V2. Though ITMX does seem a bit elevated, it has been this way for some time, but EY ST2 looks different from previous weeks this was run (last week's alog82911).

Bypass will expire:
Tue Feb 25 11:45:00 AM PST 2025
For channel(s):
    H0:FMC-CS_FIRE_PUMP_1
    H0:FMC-CS_FIRE_PUMP_2
 

Sheila, Camilla

The NLG vs OPO trans powers in 82202 didn't make sense. We thought it could be pump depletion from a high seed so we reduced Seed from 0.6 to 0.2mW. NLG measured following 76542.

125uW for NLG of 80 seemed much more sensible but when we increased the seed back to 0.6uW we got the same NLG so were not seeing pump depletion.

Plot attached shows the power in and refl off OPO, we are happy with the current OPO position and don;t think that the crystal has more losses yet.

Looking at the old data, NLGs measured on Thursday 09 January 2025:

• For 140uW, NLG was 15.8. But we are seeing pump depletion, as as soon as the Seed is injected, the OPO trans drops form 140uW to 100uW and becomes noisy, plot attached. Seed injected was 0.61.
• For 120uW, NLG was 13.3.  But we are seeing pump depletion, as as soon as the Seed is injected, the OPO trans drops form 120uW to 90uW and becomes noisy, plot attached. Seed injected was 0.61.
• The same pump depletion did NOT happen today when we had 125mW and an NLG of 80 measured, plot attached. With Seed at 0.51mW.

Next time we take NLG data, we should make sure that the seed power is low enough that the OPO trans power is steady at the requested power,  so the OPO is not experiencing pump depletion.

Sheila, Camilla

After TJ found out OPO was struggling to get enough SHG pump power to lock 82196, Sheila repeated Daniel's 82057 SHG work as he had increased H1:SQZ-SHG_GR_DC_POWERMON from 95 to 125mW but now it's down to 92mW: Tried steering the beam with picos moves, and by adjusting the temperature it improved to 93mW only.

We went only SQZT0 and Sheila adjusted the alignment into the OPO pump fiber with the OPO unlocked, bringing the the OPO REFL DC power from 1.7 to 1.9mW.   We also moved the SHG wave plate further to maximize the amount of light Now CLF could lock with controlmon around 5.8V. Much better and closer to the center of the range so should avoid this mornings 82196 issues.

Homdyne Work:

• Increased SEED power from 0.6 to 70. Subtraction was fine and we adjusted the LO waveplate to balance the LO and SEED powers.
• Measured visibility with the oscilloscope to be (1930-25.6)/(1930+25.6) = 97.4% visibility. No alignment changes needed.
• Found that the issue we saw with the LO unlocking yesterday 82153 was that  the LO loop was unstable, we reduced H1:SQZ-LO_SERVO_IN2GAIN gain, see notes below

To take the below data, SEED power reduced back to 0.6mW, and then:

• NLG measured at (Toggle SQZ/HD path and follow 76542)
• Took SQZ_MANAGER to SQZ_READY_HD (FC2 misaligned) and take data on HD DTT
• Change opo_grTrans_setpoint_uW in sqzparams.py, reload OPO guardian, take it to NO_ISS and then back to LOCKED_CLF_DUAL to check it can reach opo_grTrans_setpoint_uW
• Repeat

We measured ~6.5dB of SQZ on the HD and up to 19dB of ASQZ. Plot attached.

Next time we work on the HD, we should measure the LO loop to know the correct gain to use.

SQZ data set

• Brought opo_grTrans_setpoint_uW back to 80uW, it locked with controlmon at 6. This is now much closer to the center of the range so should avoid this mornings 82196 issues.
• Measured NLG to be: 10.2
• Before starting to take data, paused SQZ_MANAGER, turned off SQZ ASC and SQZ_ANG_ADJUST to DOWN
• FDS data and FIS data all saved to camilla.compton/Documents/sqz/templates/dtt/SQZdata_20250109.xml
• I took 4 minutes of data for FDS, then 3 minutes for FIS but only 2 minutes each for FIS ASQZ +/-10deg as we were running out of time.
• Back to observing reverted the OPO_SERVO_COMEXCEN sdf diff from dither locking, this should be turned off in SQZ_MANAGER, accepted new OPO temp.