TITLE: 07/17 Eve Shift: 2330-0200 UTC (1630-1900 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: After alignment on IOT2L wrapped up, Jennie, Keita, and I made some attempts at locking the IMC, but ultimately were unsuccessful (see alog91086 for details). I've left the IMC and JAC Guardians in 'DOWN', and I unlocked the ISS while the PSL thermalizes a bit more overnight. The LVEA remains Laser HAZARD and pumpdown of the corner and HAM1 volumes continues.

Sheila, Camilla, Ryan S, Cory (Fellow), Rahul

Given below is the summary of beam alignment work we performed in HAM7 today.

After locking the SQZ beam and the OPO we first checked the alignment on the OPO - it looked good and there was no clipping anywhere. Then we checked the beam on ZM4 and ZM5. Camilla measured the incoming beam on ZM4 to be 5.5inches approximately and it looked well centered on the iris in front of it.

On ZM5 the beam was very high on the optic (we had to remove the face baffle to be able to see the beam on the PSAMS mirror). At first we tried using  ZM4 sliders to center the beam on ZM5, but ran out of range. Hence, we mechanically adjusted ZM4 in pitch (using the pitch adjuster) to bring the beam down on ZM5 and center it (Camilla took pictures for reference). 

The beam from ZM5 to the beam divertor was off in both pitch (beam too low) and yaw (too wide as well, almost missing). We first adjusted ZM5 in yaw (mechanically) to center it on the beam divertor - we also had to push it slightly (less than 3mm) side ways for this purpose. With Yaw looking good on the beam divertor, we tried using sliders for Pitch but quickly ran out of range. I then used the mechanical pitch adjuster, but even that was not enough (ran out of range here too). Hence, I added 50grams of weight to the rear side of ZM5 intermediate mass to pitch it up (by 0.5inch) on the beam divertor. This worked and the beam looked good both in pitch and yaw on the beam divertor. 

Finally Ryan S checked the beam on the periscope and the two irises on SQZT7 table. It was off in Yaw - so I applied a negative yaw (clockwise rotation) on ZM5 mechanically (again the sliders were not enough for this big move) using dog clamps and round end screws (for better yaw control). While I rotated ZM5 in Yaw, Ryan S held an IR card on the periscope (SQZT7 table) and Camilla kept an eye on the beam, telling us when to stop. Once we were satisfied in both pitch/yaw on the periscope, Ryan S looked at the two iris in SQZT7, and he was happy with it as well.

I dogged down ZM5 and also re-attached the face baffle before closing the curtains on HAM7 chamber. Camilla started using sliders to fine tune the alignment.

Tomorrow morning I will take health checks on both ZM4 and ZM5 suspensions. 

<Channel name="H0:VAC-LY_Y1_PT120B_PRESS_TORR" low="1.0e-10" high="1.0e-05" description="VE gauge, PT120B CC">

TITLE: 07/16 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 10mph Gusts, 5mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.10 μm/s 
QUICK SUMMARY: The LVEA is currently Laser HAZARD while alignment work is happening on IOT2L and SQZT7. Power outage recovery today is essentially finished and recovery of the IFO begins.

Shoshana, Arnaud

wp 13430

CRS laser was turned back on. HOQI signals are alive, and CRS is still ringing down at 25mHz (fig 1) 

Some convention we implementend : 

1) hoqi photodiode signals calibrated in mW with calibration gain (see below) and filter was added to FM1 of the HOQI{1,2}_{SIN,COS,MCOS} filterbanks. A minus sign was added to have positive power at the output of the hoqi filterbanks (fig 2)

[1] PD sensitivity 
[2] Transimpendance Amplfier Gain
[3] 16 bit ADC 

2) hoqi distance was calibrated as per section 2 in the assembly procedure such that a positive hoqi distance signal corresponds to the retroreflector on the CRS moving away from the sensor. For this, we had to add a -1 gain in the HOQI{1,2}_DIST filterbank (fig 3)

The next two conventions not yet implemented are to match the sign of the CRS with the CPS and get the CRS tilt signal calibrated in nrad (at the CRSINF filterbank)

TITLE: 07/16 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: Outage recovery for most of the day, commissioning work ongoing on IOT2L and HAM7 as of 23:30 UTC. 
LOG:                                                                                                                                                                                                                                                                            

• 14:30 UTC Recovered CR screens
• 15:15 UTC CDS had recovered the models and let me know I was good to work on SEI/SUS
• 15:20 UTC Start to look at SUS with Oli alog91065
• 16:00 UTC TJ to reset VFD panels (CS the Ends), this didn't first the first round and he went out to do it again (open up the VFD box and reset internally instead of the exterior red/green buttons)
• 17:00 UTC Patrick and I recovered the HEPI pressures for the Ends
• 17:40 UTC Reset CS HEPI pressure after Fil restarted the 4 VFDs (again)
• 17:41 UTC PSL recovered expect for ISS (needs to thermalize) alog91066
• 18:00 UTC While recovering the ISIs we noticed a thermal error on EY ISI coil driver, TJ went out and reset it which fixed it
  • Jim was also called and he took over finishing up the SEI recovery of the CS
  • This coil driver's thermal error returned after a bit, ST1 V1 is in thermal shutdown, Dave and I watched it flip fromV!  ST1 to ST2 on the medm. alog91071
• 18:25 UTC Jennie opened the PSL light pipe
• 19:00 UTC Dave to the ends to fix the long range dolphin
• 20:15 UTC High Voltage was turned on, then the picos and heaters were turned back on. Fast shutter was turned on and verified
• 21:00 UTC Oli verified and changed if need the optics pointing based on Top Mass osems alog91081
• 21:45 UTC Re-energize rotation stage
• 22:23 UTC small power glitch, lights flickered
• 23:25 UTC HWS recovered for now...

Here is the Wednesday night power glitch which took down then vacuum pumps in the LVEA.

After restoring SUS sliders (91065), I've now gone through and restored the pointing for the top mass OSEMs for every* suspension back to where they were yesterday before the outage (around 2026/07/16 04:11:58 UTC) (NOT back to where they were during last DRMI lock since we have since changed the alignment when doing our backwards alignment for the BS). Most didn't have to move much / at all but a few did have to move quite a bit on the sliders. Suspensions that have OPLEVs, I referenced those as well, and those all lined up with addressing the top level suspension alignment. All changed alignment offset values were accepted into SDF.

* A few suspensions where I did not restore pointing to where they were yesterday are ZM4 and ZM5 since I know those are actively being worked on and I didn't want to mess up any alignments from earlier today.

lights flickered 15:23:39

Alignment into JAC was not great. Since JAC wasn't thermalized yet (heater was turned on merely 30minutes or so before we started aligning) and the fringes weren't staying put relative to the PZT voltage, I injected more than 250Vpp (with an appropriate offset) into JAC PZT to make sure that more than FSR is scanned and manually aligned JM1 and PSL PZT until 10/01 mode became less than 10% of 00 mode. Didn't bother to refine further. Attached shows the JM1 and PSL PZT alignment offsets.

I zero-ed the dark offset of JAC_REFL_A_RF43.

We had to turn on FM10 ("W_in_HAM2" which is not calibrated in reality) which was disabled at some point.

JAC guardian was able to lock JAC after the above.

We are able to see flashing in MC TRANS camera now, seems like it's mainly off in yaw but we can see 00 mode once in a while. Nothing in MC REFL camera, we'll work on IOT2L next.

I finished hooking up everything to the new CRS laser chassis (see alog 91067 and photo attached) and turned on the laser. There will be a couple of changes to be made to the chassis (swtiching which chassis the the plexi box covers, attaching stickers etc.) but for now the CRS is up and running (minus damping). I'll continue to keep an eye on it, but until the damping is hooked up it seems unlikely that it will damp down on it's own while there's still activity in the LVEA

After the power outage last night the ETMY BRSs thresholds were changed and the BRS was stuck in a damping loop again.

I've changed the H1:ISI-GND_BRS_ETMY_HIGHTHRESHOLD from 8000-->4000 and did the usual 'disable the damping from 20 minutes and then re-enable it' 

This might just be me not fully understanding the damping controls, but confusingly, when I re-enabled the damping, the BRS began to damp down despite the BRS remaining in the "BRS GOOD" state and the damping remaining off (shown in picture below, USER channel is whether damping is enabled or disabled, DAMPBIT is whether the damping is on or off.

This could be me not fully understanding the system, but it might explain why BRSY has had so many issues

At 20:40 UTC I turned off all the in-chamber illuminators that had been on for vent work (HAM3 and BSC1-3).

WP 13426

The CRS laser Chassis D2600190 was installed in rack TCS-R2. Chassis houses the CRS laser, mount, and fiber spool. A plexi security cover was installed over the chassis.

Power storm last night tripped all 3 turbos and a couple of aux carts. Pressure rose up to about 2.1x10^-04 Torr, noted on the attached plot.

As I was doing recovery work on the output mode cleaner tube turbo pump, I had just closed the main isolation valve and "reset" the box, I was taking a photo of the as found when we had the 6:01 am power glitch.

I returned to HAM1 SS-500 to check the system, it tripped, and I recovered pumping on the SS-500 system and HAM1 turbo.  Moved back to the OMT turbo pumps system, by now the main isolation valve was closed, restarted the different components and spun up the turbo pump, while this one reached "normal" speed I moved to the other two turbo stations, and repeated the process, soon we had all three turbos back up.

The aux carts were restarted for BSC1 AIP, GV5 AIP, and HAM3 AIP.

The Kobelco compressor made it back on its own, but the dryer tower did not, I restarted it and visually checked the dew point, it was good, reported by the dryer at -63 ^oC.

Attached is a plot of the pumpdown for HAM1 and the corner via PT180 signal from BSC8.

Also I have attached a video capture of the power outage, on the video you can hear the solenoid valves closing for OMT turbo station and other items.

The roughing scroll pumps were valved out and shut down for overnight.  Pressure in the corner was ~2 Torr at the break.

Wed afternoon Nergis and I went to SQZT7 to get a couple of beam profiles after the ZM4 preload was adjusted, before the ZM5 swap. 

We took two measurements with the same psams settings but different centering on ZM2, based on what Camilla and Madi did in 90946 .  The data labeled as  nominal position is for these sliders where Camila reports that the beam on ZM2 is 5.85" off the table, and the data labeled raised is for these sliders where the beam is actaully lowered to 5.75".  The center of ZM2 should be 5.5" off the table.  M^2 went from 1.35 to 1.28 horizontal and 1.25 vertical with the improved centering, and the relative astigmatism also improved from 0.13 to 0.02 Ryan found the definition of relative astigmatism on page 122 (pdf page 129) of the BC207 manual here.

ZM4 strain guage was saturated when the PZT was much above 100V, so this morning Daniel came to SQZ racks with Ryan and I and changed some resistors, Daniel will add the details.  ZM4 strain guage is now working well, with values between -4.1V to 2.7V, and Ryan turned the servo back on. 

Yesterday morning, I noticed that for some psams settings, the beam was clipping on the top periscope mirror and that then we measured quite high M^2 values.  I wondered if clipping on that persicope could explain more of our M^2 measurements.  Today Ryan Short and I carefully aligned the psams to get the beam centered on the two irises on SQZT7.  We raised the top periscope mirrors, and Ryan adjusted both periscope mirrors to get the beam well centered on the irises again.  When we did this, we noticed that only one of the bolts that holds the top periscope mount to the periscope structure was tight.  

After this Ryan and I did another round of profile measurements with the new preload and working strain guage on ZM4.  We took 5 points over the range of ZM4 with ZM5 PZT at 100V, with the ZM5 strain guage not working, then took 3 points with ZM5 at a strain guage of -4.5V which is 20V on the PZT, because the ZM5 strain guage is working there we can compare these to measurements taken before ZM5 stopped working.  

Unfortunately, even after moving the periscope mirror the M^2 values are in the range of 1.4 to 1.23, so the clipping on the periscope mirror wasn't the explanation for the high M^2