Maintenance activities have wrapped up (was extended by ~1 hour) and now starting an initial alignment. Robert will do an LVEA sweep shortly.

The LVEA remains Laser HAZARD.

I went to FCES this morning to try to troubleshoot the sort of busted H1 GS13 on HAM8. I suspect there is something going on with the cable or interface chassis, but it's not something I think I've seen before. I tried swapping cables at both the rack and the chamber, and whenever the corner 1 chassis was connected to the H1 sensor, the transfer function from the H1 CPS to the H1 sensor would be half the magnitude of the other two sensor pairs. ASDs also show the H1 GS13 has half gain when the corner 1 sensors are connected to the corner 1 chassis. However, when the H1 sensor was plugged into the corner 2 or 3 chassis, all three sensor pair tfs would have the same amplitude. I could repeat this consistently, didn't matter how I swapped the cables around, as long as the H1 sensor wasn't plugged into the correct chassis all the l2l sensor tfs would look normal.

Attached plot shows two sets of data I took during this period, red blue and light green are the normal config, dark green, pink and light blue are with the H1 sensor on the corner 3 chassis, H3 sensor on the corner 1 chassis.

I will talk to Fil, but maybe in a couple weeks we can try running a temp cable from the FC mezzanine to the chamber, and see if that changes anything.

Andrei, Camilla

We aligned the fiber polarization to minimize the H1:SQZ-SHG_GR_DC_POWERMON channel, following the instructions of Report 71761 on rotating the waveplates.

The reduction in monitor power is depicted in the attached screenshot (POWERMON_lesser_timespan.png), showing a decrease from 0.24 [a.u.] to 0.03 [a.u.].

The fiber currently in use (Fiber.png) is SM980-5.8-125 - Single Mode Optical Fiber, 980 - 1550 nm, Ø125 µm Cladding. As it seems from the figure POWERMON_large_timespan.png, power is unstable in the long term. We propose to change the fiber to PS-PM980 - 970 - 1550 nm PM Photosensitive Fiber, 0.12 NA, 6.6 µm MFD and to tightly fixate the optical cable on the optical table to furhter reduce polarization shift.

Naoki, Andrei, Camilla

We aligned the pump AOM and fiber following 72081.

We set the ISS drivepoint at 0V and measured the AOM throughput. The throughput was 34 mW/59 mW = 58%. We aligned the AOM and got 65 mW/69 mW = 94% throughput.

Then we set the ISS drivepoint at 5V and aligned the AOM to maximize the 1st order beam. The 1st order beam improved from 4.5 mW to 15.7 mW. The 0th order beam is 34.9 mW.

We set the ISS drivepoint at 0V and measured the AOM throughput again. The throughput is 51.7 mW/77 mW = 67%. Although the throughput is improved by 10%, we could not improve more than that.

Then we aligned the pump fiber. The H1:SQZ-OPO_REFL_DC_POWER improved from 3.4 to 3.7.

Minor leaks on the LN2 dewar tank/plumbing were repaired today during tuesady maintenance. Most leaks found during the LN2 tank inspection (report posted to Q2000008) were easily repaired by just tightening the connections. Joints were sprayed with liquid leak detector to confirm tightness.

The only leaks not repaired were on CP5 (Tank #8514377), leaks on the safety burst adapter. We put a wrench on the fitting and could only get ~1/16th of a turn. The threads have large amount of sealant making it difficult to tighten the fitting any more. I will ask for a quote from Norco to isolate the burst disk and repair the threads/leak.

Closing WP 11842

Tue Apr 30 10:06:05 2024 INFO: Fill completed in 6min 1secs

Gerardo confirmed a good fill curbside.

Following from BS camera reboot last night, this morning I found that ITMY (infra-red) camera was blue-screen. I also found that ITMY-Green was giving blue-screen images but its pixel-sum was changing. I rebooted both ITMY (h1cam23) and ITMY-Green (h1cam24) this morning. All three cameras are served by h1digivideo2.

TITLE: 04/30 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Preventative Maintenance
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 9mph Gusts, 6mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.21 μm/s
QUICK SUMMARY: H1 just lost lock at the end of in-lock charge measurements (SWAP_BACK_ETMX), ending a 38 hour lock. Maintenance activities have begun.

• Wind and microseism are low
• All other systems nominal

Workstations were updated and rebooted.   This was an OS package update.  Conda packages were not updated.

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 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY:
H1 is still locked and 30 hours.
Over the past 8 hour we have dropped from Observing twice for short durations due to SQZ_Manager and Camera_Servo Guardians.
We are currently Observing and intend to continue to do so until 1500 UTC.

LOG:

The Camera_servo Guardian, was getting stuck on Dither, Then it stalls.
More specifically ASC-CAM_YAW1_INMON is STUCK.

Which appears to be the BS (26) on h1digivideo2. Contacted Dave to restart the port that the camera is being provided Power Over Ethernet on.

While Dave is doing that Naoki is Running a Scan_SQZANG to optimize the SQZ angle.

Camera is now restarted and we are now in Observing!

TITLE: 04/30 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 9mph Gusts, 7mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.17 μm/s
QUICK SUMMARY:
H1 is still locked but we have fallen into commisioning due to the SQZ ISS Pump.
Looking at Alog 70050 I have requested LOCKED_CLF_DUAL_NO_ISS
I changed the opo_grTrans_setpoint_uW from 80 to 50...

Reloaded and then noticed that the comments said that 50 was too low. I was still reading comments when Naoki got onto TeamSpeak and saved the day.
He said that 70 may be appropriate but 50 is too low due to the SQZ system being tuned for 80. please see alog 72044 .

H1 Is back in Now back in Observing.



 

TITLE: 04/29 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: 17mph Gusts, 13mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.17 μm/s
QUICK SUMMARY:
H1 is Locked for 22 hours and is currently Observing. The Plan is to continue this lock throught the night.
 

TITLE: 04/29 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Mostly quiet observing day today with just one brief break for some measurements. H1 remained locked the whole shift; current stretch is just over 22 hours.

• 21:19 - Dropped observing for commissioning measurements
  • In/out of NLN_CAL_MEAS twice during this time
• 21:58 - Resumed observing

LOG:

I reran the A2L script today during our small on the hop commissioning window.

The new gains have been entered in the guardian via the a2l_gains dictionary in userapps/isc/h1/guardian/lscparams.py

'FINAL':{
            'P2L':{'ITMX':-0.9646, #+1.0,
                   'ITMY':-0.4071, #+1.0,
                   'ETMX':3.2767,
                   'ETMY':4.8886}, #+1.0},
            'Y2L':{'ITMX':2.7253, #+1.0,
                   'ITMY':-2.0093, #+1.0,
                   'ETMX':4.7658,
                   'ETMY':0.9094 },#+1.0},# Centered on the optic #removed offsets from EY IX IY 220705 gm jd ec
                    }#spots that are the center of the optic
            }#close a2l gains dict

and accepted in SDF in OBSERVE.snap, see attached images.

[Jennie, Sheila, Gabriele]

We retuned the SRCL FF, by doing the usual injections. While fitting, we just tried to change the gain of the filter that was running a bit, and that was enough to get an improved subtraction. The new filter module (FM2) is active and in guardian.

H1 dropping observing as of 21:19 UTC for ~30 minutes for quick feedforward measurements.

There had been a suggestion (passed to me by Sheila) that we should measure the beam positions on SRM and SR2 after the big move that we made this week (which is summarized in alog 77427). 

We don't have a premade script to do this like we have for the test masses, so I just did it by hand.  One at a time, I put in a line using the ADS screen to SR2 or SRM pit or yaw, then changed the corresponding A2L element to minimize the line height in CAL-DELTAL_EXTERNAL.  I was also watching SRCL_IN1 and SRCL_OUT, but the lines disappeared in the SRCL signals before they disappeared in the DARM signal, so I just used DARM. 

All A2L values for SR2 and SRM had been 0.0, so I'm not going to bother putting in a 'before' column in the table below since they were all the same value of zreo.

After finding those values, I ran /opt/rtcds/userapps/release/isc/common/scripts/decoup/BeamPosition/CalcSpotPos.py to get from A2L coefficient to beam spot.  This script had been made for IMC optics, but since SRM and SR2 are the same style, the calculation should be the same.  Reminder of where this calc comes from (it's referenced in the script): alog 31402.

We don't have any 'before' measurements to compare to, but at least we now have some amount of information of where we are on these optics after the big move.

I'm pretty sure that these new A2L values can only be good, so I've accepted them in both safe and observe snaps for SR2 and SRM (see first and second attachments, only 2 rows per SDF table are accepted).  These A2L gains for non-test mass suspensions are not under guardian control, so this should be good enough to keep them in place.

In the table below, the Cal-Deltal line reduction factor ends up really just being the ratio of the peak height in DARM before I started doing anything to that dof, and the noise level.  To do a better job of measuring this, I would have had to increase my excitation amplitude, but that didn't seem important enough to do given the limited commissioning time we had. 

I don't have time right now to think through the whole left-vs-right sign convention (it's discussed in alog 31402), but it does look like we're rather 'diagonal' in the SRC now, since the signs of the spot positions are opposite for SR2 vs SRM (eg one positive P2L and one negative P2L means the beam is on opposite sides of center).