Lockloss at 17:12 UTC during comissioning

https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1398618745

PRM and SR3 saturations before the lockloss, 2.5 hours into the lock so we still haven't been able to take a thermalized calibration measurement. The only invasive/potential LL causing work going on was some PEM tests by Robert.

Ops Day Shift Start

TITLE: 05/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.13 μm/s
QUICK SUMMARY: Just got back into Observing after a lock loss, fully auto relock. Planned commissioning today from 9-12 PT

Ops EVE Shift End

TITLE: 05/01 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: We are Observing and have been Locked for 1.5 hours. Overall quiet night with two almost fully automated relocks. Reminder that LVEA is still Laser Hazard
LOG:

LVEA is still in LASER HAZARD

22:49 Detector Locked for 52 mins and just got into Observing
22:50 Lockloss after 1m 14s Observing

22:56 Lockloss at LOCKING_ALS
23:08 Lockloss from TRANSITION_DRMI_TO_3F
23:49 NOMINAL_LOW_NOISE
23:52 Observing

03:35 Superevent S240501an

04:34 Lockloss
04:49 Lockloss from TURN_ON_BS_STAGE2
05:38 NOMINAL_LOW_NOISE
05:40 Observing                                                                                                                                                          

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
23:07	VAC	Jordan, Janos	EY	n	Turn off pump	23:26
23:46		Betsy, Brian OReilly	MY	n	Approved activity	00:46

Lockloss

Lockloss 05/01 04:34UTC

Ops Eve Midshift Status

Have been Locked and Observing for almost 4 hours, and just got a notification about superevent S240501an

Ops Day Shift Summary

TITLE: 04/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Busy maintenance day, but the initial alignment and lock acquisition that followed were straightforward. Lost lock shortly after starting to observe.

• 14:58 - Lockloss at the end of in-lock SUS charge measurements
• 20:24 - Maintenance finished, starting initial alignment
  • Needed to move SRM in yaw quite a bit to lock align SRC
• 21:17 - Alignment finished, starting lock acquisition
• 21:58 - Reached NLN; fully automated acquisition
• 22:49 - Started observing after tuning SQZ and A2L
• 22:50 - Lockloss; no immediately obvious cause

The LVEA remains Laser HAZARD for more potential viewport tests during commissioning time this week.

LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:30	FAC	Chris, Tyler	MX, MY	-	HVAC fan greasing	15:35
15:00	CAL	Jeff	LVEA	-	HAM6 racks	15:45
15:01	FAC	Kim, Karen	FCES	-	Technical cleaning	15:33
15:03	FAC	Mitchell	MX	-	Grabbing case	15:18
15:10	VAC	Gerardo	MX, EX	-	Turbopump checks	17:40
15:11	SAF	LASER HAZARD	LVEA	YES	LVEA is LASER HAZARD	Ongoing
15:13	SAF	TJ	LVEA	YES	Transition to HAZARD	15:19
15:15	FAC	Eric	MER	-	Heating coil maintenance	17:22
15:16	ISC	Sheila, Jennie, Minhyo	CR	-	Single bounce measurements	20:40
15:18	VAC	Jordan, Janos	All	-	CP tank repairs	17:05
15:18	VAC	-	EY	-	Dewar jacket pumping	17:05
15:22	ISC	Jenne +1	LVEA	-	Tour	15:50
15:26	IAS	Jason, RyanC	LVEA	-	FARO surveying	18:46
15:28	SAF	Travis	All	-	Captial inventory	16:56
15:33	FAC	Karen	EY	-	Technical cleaning	16:30
15:33	FAC	Kim	EX	-	Technical cleaning	17:21
15:34	SEI	Jim, Mitchell, TJ	LVEA	-	Craning 3IFO storage container	17:15
15:35	FAC	Tyler	OSB Roof	-	Inspection	16:00
15:37	PEM	Robert, Anamaria	LVEA	YES	Beam hunting (VIEWPORTS OFF)	20:09
15:51	FAC	Ken	FCTE, LVEA	-	Cable tray installation	19:02
15:51	SAF	Fil	All	-	Interlock checks	18:35
16:01	FAC	Tyler	EX	-	Checking for bees	17:22
16:02	CAL	Jeff	LVEA	-	Getting SR785 data	16:07
16:41	SQZ	Camilla, Naoki, Andrei	LVEA - SQZT0	YES	Adjust SHG pump AOM/fiber	18:10
17:21	FAC	Karen, Kim	LVEA	-	Tech clean	18:45
17:22	FAC	Tyler	OSB roof	n	Checking roof status	17:28
17:40	VAC	Gerardo	LVEA	-	Capital inventory	18:52
17:44	ISC	Sheila	LVEA	-	Turning off sidebands	17:50
17:52	SEI	Jim	FCES	-	Troubleshooting HAM8 GS13	18:56
18:15	IAS	Tyler	LVEA	-	FARO surveying	18:40
18:49	SUS	Jason	LVEA	YES	Troubleshooting ITMX oplev	18:59
19:00	ISC	Sheila	LVEA	-	Turning sidebands back on	19:04
19:37	SQZ	Terry, Kar Meng	Opt Lab	LOCAL	SHG work	Ongoing
19:52	VAC	Gerardo	MY	-	Capital inventory	21:09
20:12	FAC	Ken	FCTE	-	Electrical work	21:12
20:20	PEM	Robert, Anamaria	LVEA	-	Cleanup & sweep	21:39
20:00	CDS	Dave	EX, EY, CER	-	Looking for laptops	20:54

Lockloss

Lockloss at 04/30 22:50 UTC from unknown cause

Ops EVE Shift Start

TITLE: 04/30 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 8mph Gusts, 6mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.23 μm/s
QUICK SUMMARY:

Have been Locked for 52 minutes and just got to Observing

X-Mid and X-End FAMIS Task for Turbo Pumps

Functionality test was done on the following stations:

X-Mid turbo pump station;
     Scroll pump hours: 215.2
     Turbo pump hours: 125
     Crash bearing life is at 100%

X-End turbo pump station;
     Scroll pump hours: 7143.2
     Turbo pump hours: 1093
     Crash bearing life is at 100%

FAMIS tasks 24850 and 24874.

OMC Scans to investigate possible OFI bad throughput

Jennie W, Sheila

 

Today we took OMC scans to help diagnose what is going on with our alignment through the OFI - that is, what is the mode-matching at our the old alignment (as of Monday 22nd) and our new alignment (as of this morning).

 

Sheila turned off the sidebands before the test and we had the ETMs and the ITMX mis-aligned initially for single bounce configuration.

 

Old alignment: SR3 M1 YAW OFFSET = -125 microradians

SR3 M1 PIT OFFSET = -437 microradians

SR2 M1 YAW OFFSET = -421 microradians

SR2 M1 PIT OFFSET = -64 microradians

 

Due to PEM measurements we switched from single bounce off ITMY to single bounce off ITMX.

 

Locked time = 1 minute from GPS 1398534847

Unlocked time = 1 minute from GPS 1398534984

Scan = 200 s starting at 1398535070 GPS

 

New alignment: SR3 M1 YAW OFFSET =  120.2 microradians

SR3 M1 PIT OFFSET = 437.9 microradians

SR2 M1 YAW OFFSET = 2061.7 microradians

SR2 M1 PIT OFFSET = -5.5 microradians

 

Locked time = 1 minute from 1398538330 GPS

Unlocked time = 1 minute from 1398538461 GPS

Scan = 200 s starting at 1398537927 GPS

Dark time with IMC offline and fast shutter closed = 1398538774 GPS

 

Mode mis-match measurments pending...

 

ITMX and ITMY oplev shifts after incursion

Robert, Jason, Anamaria

Today we used the oplev to determine the CP alignment for both ITMX and ITMY. We had to move the sender around to find all the beams so here I mark the shift in the beam location in case someone later wants to look at drifts. The ITMs were realigned slightly after our test so it's not good to 1urad but the oplevs drift around more than that anyway. I also had to choose times after lockloss and before relocking, to not have ASC interfere.

	ITMX P	ITMX Y	ITMY P	ITMY Y
Before	-8	-1	-20	1
After	-10	5	6	2

Since people don't open the receiver box or the sender box very often we note:  
a) The beams on the oplevs are as large as the QPD which is not great, but depends what they're used for.
b) We found the ITMX oplev beam to be clipping on the nozzle baffle. Jason helped us shift the QPD and then we realigned to this new, more central location.
c) Replacing the sender cover is very difficult without causing a shift in the oplev beam, though we were quite careful to not touch the telescope while doing that. This is why we were not able to center them better.
d) I suppose the last few urad should be done with the QPD stages, but one has to be careful to check from time to time that it doesn't walk out of the aperture over time (which is smaller since the installation of nozzle baffles).

Walking the beam on the OFI

Jennie W, Sheila, Minhyo

 

Summary: We tried to walk the beam on the OFI with SR2 and 3 and cannot find another 'good spot' at least with moves in yaw of the SRC cavity axis.

 

Today we set the IFO up in single bounce with 10W input and ITMX mis-aligned. Then we moved the sliders back to what they were before Jenne made changes to them on Wednesday

Then we stepped SR2 down in yaw in steps of about 0.6 - 1.0 uradians and compensated for this movement on AS_C QPD by moving SR3 down in yaw also to recentre. Eevery few steps we had to tweak the pitch of SR2 or 3 in pitch as well as pitch motions of the SRs are slightly cross-coupled with yaw motions on the QPD.

Jeff then pointed out we should be moving SR3 first, as this is the mirror closest to the OFI so I switched to moving this mirror first and then SR2 to compensate. We tried to move the same amount down on SR3 that Jenne moved. The power got worse on AS_C, only imrpoving when we were very mis-centred in yaw on this QPD so that is not a good reference.

See a zoomed in image of the steps in SR2 and 3 and the effect they had on ASC-AS_A_DC_NSUM and ASC-AS_C_NSUM.

From this it looks as though the power throughput to ASC-AS_C (anti-symmetric port) was maximum when we were well-centred on ASC-AS_C just after the first cursor before we had started walking the beam.

I think this suggests that there is no small burnt spot in this degree of freedom across the OFI surface that we can walk to the other side of and see our throughput improve.

However the beam looked cleaner at points when it was positive in yaw on the QPD - not sure if this was real or not.

After these moves we reverted back (first cursor) to the alignment sliders we had before Jenne's moves on Wednesday 24th and took an OMC scan.

Then we went back to the 'nominal' alignment from this morning (second cursor) before maintenance started and took another OMC scan.

 

Translating SQZ beam for better AS_C alignment adn OMC thoughput

Naoki, Sheila, Camilla

After the output alignment shift reported in 77427, we tried to revert SQZ to the last successful SQZ-OMC scan in 77515 but when we increased throughput, AS_C alignment was bad. Today we translated the beam to get good throughput on AS_A/B and AS_C and a centered beam on AS_C with OMC DC centering loop running. This was a move of ZM4 -1000urad, ZM5 -650urad in yaw as reported by DAMP_Y_INMON channels

• We reverted all alignment sliders (ZM4,5,6 OM1,2,3 SRM) and PSAMS to April 16th (leaving PSAMS at 7.5V/0.55V pre-77268).
• Naoki injected the same amount of SQZ SEED power as previous OMC-SQZ scan
• We translated in YAW by yawing ZM5 negative 50urad to increase AS_A power and then yawing ZM4 negative to bring the beam back centered to AS_C. Tried the positive ZM5 direction beforehand and it got worse.
• At 19:49UTC we turned on the OMC DC centering loops.
• We had god throughput at 19:59UTC and  moved until we made things worse at ~20:00UTC and then backed off.
• Total ZM4,5 changes attached, sdf's attached.
  • Before 1st t-cursor is moving from optimum in-lock sqz to April 16th OMC-SQZ alignment.
  • Between t-cursors is our translation. We moved ZM4 -1000urad, ZM5 -650urad. ZM4 is at 24,000 counts out of available 32,000.

Attached shows previous April 16th OMC-SQZ scan compared to during today's translation and how we left the ZMs:

• AS_C power is similar (new 373 vs old 385). Around ~3% percent lower, it almost seemed correlated with oscillations in YAW which isn't good as could suggest some yaw clipping remains.
• AS_A/B power is similar/increased,  AS_A (new 74 vs old 75) and AS_B  (new 80 vs old 75). They were not the same as each other similar but this can be explained by the AS_C being  0.2 to 0.4 off in PIT and YAW in the April 16th scan.
• Centered on all AS_A/B/C PDs.

We're not sure how this change will effect in-lock SQZ as Vicky had to make big changed in 77400  and we may have seen that good OMC scan alignment isn't good SQZ alignment?

re-ran A2L script

This morning I came into the control room as the magnetic injections were finishing, and ran the a2l script while the charge measurements ran.

I did this because after Jennie Wright ran A2L yesterday afternoon it was not well tuned: 77495

When Jennie ran it yesterday, the coherence was over the threshold for all 8 gains, so all 8 were adjusted.  This morning I ran it and the coherence was below threshold for ITMX P2L and ETMY Y2L, so those were not updated.  I increased their amplitudes in the run_all_a2L.sh script, but as I was re-running the IFO unlocked due to the charge measurements.

The attached screenshots show how it changed the optics that it did run for, this is a large difference from the values that Jennie got yesterday.  Jennie W ran the script 20 hours into the lock, while I ran it 37 hours into the same lock, so these were both with a well thermalized IFO. 

It seems that there may be two problems we are facing with tuning A2L, one that our process doesn't seem to always work well to minimize A2L, and second that it seems that the values may be changing over the course of a lock.

Restarted picket-fence, it has stopped 03:37:04 UTC Sun 28 April 2024

Another picket fence issue at 03:37 UTC, I think the third in the past few weeks. I restarted the process on nuc5.

Step in Clean range around 5:20 this morning

There was a drop in clean range around 5:20 this monrning, which doesn't seem to be a reapeat of the output arm shift we had earlier this week. 

Attached is a trend of the DARM blrms (based on DARM error, no calibration corrections or cleaning) and comparison of the cleaned and corrected range against the CAL-DELTAL range, only the cleaned channel sees the drop.  This made me concerned that we had a drop in optical gain, but the trend of the time dependent calibration correction factors doesn't show anything happening at this time. 

I don't know what would cause a sudden change in the clean range, since I don't think that the jitter subtraction would cause a sudden change like this.

OMC alignment scan started

started scan of OMC alignment started with no squeezing: April 26th 2024 16:36:47 ended at 17:30 UTC