[Joe B, Vlad B, You-Ru Lee]
We've been trying to understand a ~5% systematic error in the LHO calibration for awhile now.  After eliminating possibilities one by one, Vlad found that the H1:SUS-ETMX_L1_LOCK_L, FM6 aL1L3 filter definition in our calibration model (as well as in the h1calcs front end model) did not match the actual interferometer's definition.  Specifically, a 50 Hz pole had been changed to a 30 Hz complex pole pair on March 20th, 2024.  See LHO alog 76546.

Even though the UIM is rolled off relative to other stages quite a bit by 30 Hz, it still has a several percent contribution to the overall interferometer response there, so a ~50% error at 30 Hz due to the filter shape can contribute significantly to the overall error.

The other contributing factor is the SRC detuning effects, which up until this point have been neglected when pushing updated calibration models to the actual pipeline.

We've been looking at early September, as that is part of the time we need to regenerate due to poor 60Hz subtraction injecting noise, and specifically wanted to eliminate this small but noticeable systematic.

When I combine the fit September SRC detuning (specifically report 20240905T200854Z), along with an updated foton file (specifically ligo/svncommon/CalSVN/aligocalibration/trunk/Common/H1CalFilterArchive/h1susetmx/H1SUSETMX_1394948578.txt instead of H1SUSETMX_1394415894.txt), I get the attached plot, which seems to agree with the PCAL monitoring lines we run all the time still.  Still some residual mismatch, but I didn't do a particularly good job of lining up the average kappa values I applied and the grafana page, but it certainly will flatten out the large bump and phase wiggles at 30Hz and below.  The monitoring line data comes from Maddie's monitoring line grafana pages.

Still a bit more work to be done, and comparisons at other times, but we should aim to fix this next week.

Fri Feb 14 10:14:47 2025 INFO: Fill completed in 14min 43secs

Gerardo confirmed a good fill curbside. TCmins [-58C, -56C] OAT (0C, 32F) DeltaTempTime 10:14:47

H1 back to observing at 16:47 UTC following a small-ish ETM glitch lockloss at 14:47 UTC. Fully automatic relock with an initial alignment.

After some time at NLN, I noticed the DCPD sums growing and traced it to ETMY violin mode 20 ringing up. Turning off the gain (nominally -1.0) stopped it from rising. After 15 minutes or so, I tried just a sign flip for the gain (so, 1.0) and so far that seems to be damping the mode down. Will keep an eye on this today. [OpsInfo]

FAMIS 26361

Laser Status:
    NPRO output power is 1.849W
    AMP1 output power is 71.66W
    AMP2 output power is 140.0W
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 9 days, 20 hr 1 minutes
    Reflected power = 23.27W
    Transmitted power = 105.7W
    PowerSum = 129.0W

FSS:
    It has been locked for 0 days 0 hr and 35 min
    TPD[V] = 0.6391V

ISS:
    The diffracted power is around 3.5%
    Last saturation event was 0 days 0 hours and 35 minutes ago

Possible Issues:
    PMC reflected power is high
    FSS TPD is low

RefCav alignment has taken a dive over the past few days (see trend); if there's a chance in the coming days I can try tweaking up the alignment.

TITLE: 02/14 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 8mph Gusts, 5mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.42 μm/s
QUICK SUMMARY: H1 looks to have lost lock at 14:47 and is in the process of relocking, currently just locked DRMI. Several ALS locklosses before H1 decided to run an initial alignment, which went automatically.

• A few inches of snow on-site with a light amount still coming down
• Wind is low, secondary microseism just below 90th percentile

BS Camera stopped updating just like in alogs:

• 79685 My alog noting the issue for me back in Aug 2024.
• 79648 Dave's Solution

This takes the Camera Sevo guardian into a neverending loop (and takes ISC LOCK out of Nominal and H1 out of Observe).  See attached screenshot.

So, I had to wake up Dave so he could restart the computer & process for the BS Camera.  (Dave mentioned there is a new computer for this camera to be installed soon and it should help with this problem.)

As soon as Dave got the BS camera back, the CAMERA SERVO node got back to nominal, but I had accepted the SDF diffs for ASC which happened when this issue started, so I had to go back and ACCEPT the correct settings.  Then we automatically went back to Observing.

OK, back to trying to go back to sleep again!  LOL

ALS EY WFS F9's came up as (2) SDFs.  Accepted (see attached).

The last lockloss was most likely due to an EQ (Equador?).  I was already up, so I stayed up to proactively run an alignment and got almost done with SRC OFFLOADED but H1 Manager took ALIGN IFO DOWN (!!!!) and started comepletely over---I guess I shoudl have taken H1 Manager down? 

At any rate, ran a manual alignment for SRC again & H1 made it back up all the way except for the ALSey diffs.  OK, back to bed.

TITLE: 02/14 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY:

IFO is in NLN and OBSERVING as of 02:07 UTC.

Very calm, quiet shift with an automatic full lock.

LOG:

None.

Jennie W, Sheila, Jim, Robert

tl;dr: HAM1 motion as measured by table-top L4Cs is at least an order of magnitude below DARM.

I have been using Sheila's power projection code to work on analysing Robert's shaker measurements on HAM1 chamber in October last year. Below is the injection info from Robert. The shaker was on top of one of the chamber HEPI tables.

"A line at 25 Hz was injected by shaking HAM1 for nearly 20 minutes starting at 30/09/2024 18:02:00 (DTT notation). This was one of the injections used to determine which HAM had the vibrational coupling.After determining  that the Coupling was at HAM1, we made A 20-26 Hz  "wide band" injection with a strong resonance peak at about 23 Hz, for about 5 minutes starting at 31/10/2024 18:20:57."

The attached plot shows the projection of HAM1 noise as measured by the table-top L4C in the x direction (beam propagation direction). The DARM noise measurement over this range is shown in blue and the projection in green. DARM was taken from H1:CAL-DELTAL_EXTERNAL_DQ and is not calibrated. This part of the code needs further work so this projection is valid but its absolute value should not be compared to other noise budgets without fixing this error.

The code can be found on my branch of Sheila's code as ham1_coupling.py.

The second image shows the ASDs I used in DTT. The 30th September shaker injection was only done at 25 Hz so I just used the broadband injection between 20 and 26Hz from the 31st of October to make the projection. The quiet time was taken directly after the measurement stopped in the same lock. The top plot is DARM and the bottom is the table-top L4Cs in units of nm/sqrt(Hz) as Jim calibrated them from velocity units these channels are in with three poles at 0Hz and two zeros at 0.707 Hz.

The data is in /ligo/home/jennifer.wright/git/2025/HAM1_Coupling/20250121_HAM1_Coupling_excess_power_proj_bb.xml and the ndscope I used to find the times is in the same folder called HAM1_coupling.yaml.

TITLE: 02/14 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Earthquake
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: EARTHQUAKE
    Wind: 14mph Gusts, 10mph 3min avg
    Primary useism: 1.25 μm/s
    Secondary useism: 0.31 μm/s
QUICK SUMMARY:

IFO is in IDLE due to EARTHQUAKE

Just got an incoming 5.8 EQ from Alaska. After this passes, we will return to locking.

Jennie W, Robert,

As part of Robert's viewport measurements today he and I measured the power at the HAM3 viewport after PR2 spot moves earlier this week.

We moved the power head about a bit to see the maximum measurable power which was about 3.49mW. We left this power meter plugged into a yellow extension cord in the clean room as it seems to have an almost dead battery and needs recharged.

TITLE: 02/13 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Unlocked
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: LVEA temperature changes were a bit topic today, there have been some changes made to averaged sensors used and soem of their setpoints. EX is also rising a bit in the VEA atm.

The beginning of the shift was spent trying to get ALSX to lock. Eventually, Sheila and others went out onto ISCT1 and shimmed up the TRX DCPD to get more light on the PD without interferring with the PR3 alignment (alog82783). This is intended as a temporary solution. ALSX locked without issue after this and then there was a brief commissioning period. The SQZr briefly knocked us out of observing, but Camilla and I bumped the threshold a bit lower and it was able to relock (alog82789). We just lost lock from an earthquake from Alaska. Sad.
LOG:

• 1909 Back to low noise, commissioning time
• 2018 Observing
• 2046-2101 Out of observing to fix SQZr

Closes FAMIS 26360. Last checked in alog 82661.

While all trends are below the threshold, EX FAN2 1 and 2 seemed to have some weird fluctuating behavior jumping from near 0 to 0.3 and back down many times in only 36 hrs.

Additionally, MR FAN6_170_1 signal went up very slighlty (<0.05 change) and seems to be visibly noisier as of 5 days ago.

Screenshots attached.

Back to Observing after a lock loss and some commissioning time.

New Y2L PR2 gain SDF accepted. This might need to be accepted in the SAFE.snap as well.

Camilla, Sheila

As Sheila/Daniel did in 82057, I touched the SHG steering picos (plot) and temperature (this was annoying and not clear) but could only increase SHG power form 105 to 107mW. Our best is ~120mW. We've seen this before with LVEA temp swings.

Couldn't lock with OPO trans at 75uW (Ibrahim reduced from 80uW in 82761) so I further reduced to 70uW as in wiki and adjusted OPO temp. H1:SQZ-OPO_ISS_CONTROLMON is at 1.5V so not great but hopefully good enough especially as the LVEA temperature stabilizes.

We also increased the SQZ_ANG_SERVO gain back form 0.1 to 0.5, undo-ing part of Sheila's Feb 3rd edit.

Matt, Sheila

we pico'd on the HAM3 ALS/pico to try to get better centered on the LSC pop diode.  We did this while the IFO was thermalized, so it was a little hard to tell if we've restored the power to what it was before our moves.  We looked at coherence similar to 81329  today our clipping isn't bad enough to show up as a reduction in coherence as was seen there.