TITLE: 06/10 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Commissioning
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 16mph Gusts, 13mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.18 μm/s
QUICK SUMMARY:

We are Locked and just finished another set of calibration measurements

Following instructions from 76751 I ran a CARM OLG measurement after we had been at high power for a bit more than 4 hours, see attached. The most recent comparison I can find for low noise is 80956, it looks like we would want to increase the gain by roughly 6dB to get back to a 17 kHz ugf as seen there.

Randy, Ibrahim

Today, Randy an I fit checked the BBSS Structure Support Plate (D2500013) and the Lifting Bar Assembly (D1100802) for the BBSS. 

Overall, everything fit. See pictures below. Some relevant notes:

• BBSS Sctructure Support Plate fits around the BBSS unobstructed (Only obstruction is the HRTS Homodyne which will not be there)
• Structure Support Plate also fits fully in the BBSS container (width of plate is 31.5" and width of container is 31.75" so 0.25" clearance total).
• Installed Helicoils (3/8-16 x1.5D) on the Support Plate
• Lifting Bar assembly mounts with the arms of the lift with no obstructions
• Lifting Bars also fit fully in the container (width of bar edges is 31.5" and width of container is 31.75"
• BBSS with side Vibration Absorbers do not fit within the container (2" too wide) so must be removed prior. This is the only thing we saw that needs to move.
• Confirmed the height at the lift point (and where the support plate lies) is sufficient for the BBSS height.
• Randy operated the lift and found it to be very smooth and easy to use.

No SQZ time taken today, 21:47:00UTC to 21:59:00UTC.

At the beginning of the vent in early April all the CDS WAPs were turned on and left on. The CDS SDF was updated to that configuration.

Today all but the MSR WAPs were power off, and we have returned to the O4 SDF configuration for these channels.

running calibration sweep #2
pydarm measure --run-headless bb
2025-06-10 13:47:53,831 config file: /ligo/groups/cal/H1/ifo/pydarm_cmd_H1.yaml
2025-06-10 13:47:53,846 available measurements:
...
~ computer noises ~
...
notification: end of test
diag> save /ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250610T204753Z.xml
/ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250610T204753Z.xml saved
diag> quit
EXIT KERNEL

2025-06-10 13:53:04,389 bb measurement complete.
2025-06-10 13:53:04,389 bb output: /ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250610T204753Z.xml
2025-06-10 13:53:04,389 all measurements complete.

anthony.sanchez@cdsws29: gpstime;python /ligo/groups/cal/src/simulines/simulines/simuLines.py -i /ligo/groups/cal/H1/simulines_settings/newDARM_20231221/settings_h1_20250212.ini;gpstime
PDT: 2025-06-10 13:55:32.403757 PDT
UTC: 2025-06-10 20:55:32.403757 UTC
GPS: 1433624150.403757
2025-06-10 20:55:33,268 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250610T205533Z.hdf5

...
~ computer noises ~
...

2025-06-10 21:18:03,494 | INFO | Ending lockloss monitor. This is either due to having completed the measurement, and this functionality being terminated; or because the whole process was aborted.
2025-06-10 21:18:40,400 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250610T205533Z.hdf5
2025-06-10 21:18:40,409 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250610T205533Z.hdf5
2025-06-10 21:18:40,415 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250610T205533Z.hdf5
2025-06-10 21:18:40,420 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250610T205533Z.hdf5
2025-06-10 21:18:40,426 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250610T205533Z.hdf5
PDT: 2025-06-10 14:18:40.573696 PDT
UTC: 2025-06-10 21:18:40.573696 UTC
GPS: 1433625538.573696

Here is an executive summary of the ASC changes that have been made, why they were made, and the potential impact on the noise:

• DHARD P boost is currently disengaged
  • as a part of investigating a still-mysterious 1 Hz instability, I disengaged FM8, which is usually engaged in LOWNOISE_ASC.
  • This boost was designed by Gabriele to reduce the DHARD P RMS, which was beneficial to reducing the DARM RMS
  • This may overall impact the DARM RMS
• MICH P and Y have been reverted to an older loop design
  • during locking, some 0.5 Hz ring ups in the MICH ASC impacted locking, even causing a lockloss
  • I changed the loop design back to a design that was in place pre-O4, which uses FM7 instead of FM10 in MICH and FM5 instead of FM10 for MICH Y
  • This may result in more MICH ASC noise coupling to DARM
  • Changing back to this old design has reduced the RMS in MICH P and Y
• Disengaged BR filter in MICH P and Y
  • I disengaged a bounce/roll filter in the MICH ASC that had been added during O4. We disengaged this same filter in the MICH LSC
  • We may see the beamsplitter B/R modes in DARM, but unlikely because we have dampers on the BS for this
• A new DC centering loop, DC6
  • centers the beam on POPX using PM1
  • likely very low coupling to DARM
• PRC2 ASC is now on POPX
  • this would change the noise in the loop, however PRC2 has very low coupling to DARM, unlikely to impact noise

I ran a coherence in NLN with all the arm loops, MICH and PRC2 ASC. There is some coherence with CHARD P, and with MICH P and Y that would be worth investigating with a noise budget injection.

Sheila pointed out that the green reference resetting that I did yesterday (alog 84902) maybe didn't need to have the green QPD setpoints set, and should just have needed the camera nominal values set. 

This morning I did a bit of trending, although I think there is more to do if someone wants to take that on.  In the attached screenshot (not super readable, since I had to run to a meeting, sorry!) the Y-cursors are set to the values of the various signals just after I reset the green refs yesterday.  Then the data traces that are visible in the plots are from the most recent reference setting before that, before we reseated the HAM1 door. 

The TMS pitch and yaw values are all about 1 urad different between the two times (I seem to have zoomed too much on the TMSY Y plot though).  The green QPDs, particularly the Xarm pit A and then both the Xarm yaws changed. The camera offsets didn't chage much, although they did change a bit.

Anyhow, no major conclusions here, more just posting as a 'project started, someone is welcome to pick it up from here if they want to before I get back to it'.

I just checked the efficacy of the jitter noise cleaning.  Obviously we'd prefer to mitigate this in hardware, but it still seems useful to check up on.

There are still several vacuum pumps running near HAM1, so hopefully these jitter peaks won't be as prevalent once they get turned off in a few days. However, until then, it looks like the cleaning coefficients from before the vent are still good.  This makes some sense, in that we didn't do a lot that would change our coupling of the jitter noise into the interferometer dramatically. 

For now, I'll leave the noise subtraction as it was before the vent, with no changes.

Broadband:

Start: 1433619864 / 2025-06-10 12:44:06

Stop: 1433620174 / 2025-06-10 12:49:16

Simulines:

GPS start: 1433620215.301202

GPS stop: 1433621616.185126

2025-06-10 20:13:18,020 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250610T194958Z.hdf5
2025-06-10 20:13:18,028 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250610T194958Z.hdf5
2025-06-10 20:13:18,035 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250610T194958Z.hdf5
2025-06-10 20:13:18,040 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250610T194958Z.hdf5
2025-06-10 20:13:18,045 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250610T194958Z.hdf5

I'm working on going through some Observe SDFs, so that we're ready for observing soon.

• The IMC ASC PZT has been changed, so accepting that.
• A lockin oscillator in the LSC model had a ramp time change - I've reverted it.
• The CAL-INJ_TRANSIENT input switch is off, which double-disables hardware injections.  From Nov 2024 - Apr 2025, the input switch was on while the output was off.  I'm accepting that the input is off in addition to the output being off.  This matches the safe.snap.  This switch probably got left on when we last did some hardware injections - but it doesn't matter since the output is always correctly off.
• The ITMY reaction chain alignment offsets are now zero in the safe.snap file since we aligned it in vacuum.  I've accepted those values in the observe.snap file.
• I accepted the current value for the ISS' picomotor 8 speed setting.  The picomotor is disabled, it really doesn't matter at all, but this way I don't have to turn on the motor or anything.  This was last used to pico onto the ISS array last week.

Jim is currently working on going through many of the SEI SDFs.  The rest of the diffs I need to check with other commissioners to be sure about before we clear them, but I think we're getting close to having our SDFs cleared!

I went down to end Y to retrieve the usb stick that I remotely copied the c:\slowcontrols directory on h1brsey to, and also to try to connect h1brsey to the kvm switch in the rack. I eventually realized that what I thought was a vga port on the back of h1brsey was probably not, and instead I found this odd seeming wiring connected from what I am guessing is a hdmi or dvi port on the back of h1brsey, to some kind of converter device, then to a usb port on a network switch. I'm not sure what this is about, so I am attaching pictures.

Tue Jun 10 10:12:01 2025 INFO: Fill completed in 11min 57secs

Sheila, Elenna, Camilla

Sheila was questioning if something is drifting for us to need an initial alignment after the majority of relocks. Elenna and I noticed that BS PIT moves a lot both while powering up /moving spots and while in NLN. Unsure from the BS alignment inputs plot what's causing this.

This was also happening before the break (see below) but the operators were similarly needing more regular initial alignments before the break too.  1 year ago this was not happening, plot.

• Now:
  • While locking (Power up state #500 to NLN #600) BS PIT moves 40urad  plot
  • During a 2hr lock BS PIT moves 13urad plot
• Before Break:
  • While locking (Power up state #500 to NLN #600) BS PIT moves 43urad  plot
  • During a 4hr lock BS PIT moves 20urad plot

TITLE: 06/10 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 1mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.18 μm/s
QUICK SUMMARY:
H1 was in IDLE when I arrived.
I will start trying to lock now.
 

[Jenne Louis Matt]

The change in the filters used by calibration created a 10% calibration error. Louis is trying to fix this but in an effort to have a way to revert to the previous filters without losing lock Jenne came up with a cdsutils way to revert back. Essentially it toggles off the new filters ('H1:OMC-DCPD_A0 FM10 H1:OMC-DCPD_B0') FM10 and steps the demod phase ('H1:OMC-LSC_PHASEROT') in steps of 1 degree, 77 times, with a 0.065 sec delay (77steps/5seconds) between each step. The filter toggles have a 5 second ramp time, which informs the step delay in the cdsutils step, and the 77 degrees is the difference from the old demod phase and the new. Hopefully this avoids a lockloss in the event we are to revert, but may not. *fingers crossed*

Here is the command:

UPDATE:

It worked :) anti-alias filters off and OMC-LSC phaserot returned to nominal