Lockloss @ 01/20 04:37 UTC after over 13 hours locked

Observing and have been Locked for 10 hours now. Nothing to report.

TITLE: 01/19 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Quiet day with H1 observing for the duration and one candidate superevent. H1 has now been locked for almost 6 hours.

• 19:02 - S250119cv

TITLE: 01/19 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 159Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 7mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.24 μm/s
QUICK SUMMARY:

Observing and have been Locked for almost 6 hours.

Sun Jan 19 10:04:19 2025 INFO: Fill completed in 4min 16secs

TCmins [-65C, -64C] OAT (-1C, 30F). I'm testing delta-temperature based trip code in parallel, it tripped at 10:04:21.

At 02:31 PST this morning we had a slight vacuum glitch at EX originating at X2-8 (beam tube 220m from EX). Gas levels were low, well below VACSTAT trip levels. Pump down time was about 6 minutes. Attached plot show a coincident drop in H1 range at this time.

Second plot shows a similar correlation for an EX glitch on Sat 11 Jan 05:45 PST.

TITLE: 01/19 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 5mph Gusts, 2mph 3min avg
    Primary useism: 0.07 μm/s
    Secondary useism: 0.34 μm/s
QUICK SUMMARY: H1 has been locked and observing for 20 minutes. Range is lower than I'd expect, but perhaps it will come up as things thermalize. Looks like H1 lost lock at 13:41 this morning from an unknown cause (no sign of ETM glitch that I can see) and relocked itself after running an initial alignment.

• Wind is low, secondary microseism slightly higher than yesterday just under 90th percentile
• All other systems nominal

TITLE: 01/19 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY: Currently Observing at 157 Mpc and have been Locked for almost 40 hours. Quiet night where the only thing that happened is that I got my third superevent candidate of the weekend!!
LOG:

02:51 Superevent candidate S250119ag

Observing at 155Mpc and have now been Locked for 35.5 hours. Secondary microseism is on the rise but not too bad yet. Nothing to report.

TITLE: 01/18 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 161Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 3mph Gusts, 1mph 3min avg
    Primary useism: 0.06 μm/s
    Secondary useism: 0.25 μm/s
QUICK SUMMARY:

Observing at 161 Mpc and have been Locked for almost 31 hours. I'll keep an eye on ETMY mode1, but it's looking good right now.

TITLE: 01/18 Day Shift: 1530-2100 UTC (0730-1300 PST), all times posted in UTC
STATE of H1: Observing at 160Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Locked for 30.5 hours. Violin mode ETMY mode 1 was rung up this morning, but changing the damping to no phase and -0.2 gain has damped the mode down nicely. Coordinated calibration measurements were run and other than that we have been observing the whole time.
LOG:

• 1933 Out of observing for calibration measurement
• 2004 Observing

Ran the usual coordinated calibration sweep following the wiki. The IFO has been locked for 29 hours.

Simulines start:

PST: 2025-01-18 11:39:53.237752 PST
UTC: 2025-01-18 19:39:53.237752 UTC
GPS: 1421264411.237752

Simulines end:

PST: 2025-01-18 12:05:08.721297 PST
UTC: 2025-01-18 20:05:08.721297 UTC
GPS: 1421265926.721297

Files:

2025-01-18 20:05:08,547 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250118T193956Z.hdf5
2025-01-18 20:05:08,565 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250118T193956Z.hdf5
2025-01-18 20:05:08,576 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250118T193956Z.hdf5
2025-01-18 20:05:08,587 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250118T193956Z.hdf5
2025-01-18 20:05:08,598 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250118T193956Z.hdf5

Sat Jan 18 10:04:21 2025 INFO: Fill completed in 4min 18secs

TCmins [-69C, -67C] OAT (0C,32F)

Violin mode ETMY mode 1 was turned off via the VIOLIN_DAMPING gaurdian around 05UTC last night, log excerpt below. Leaving it with no gain had it not increasing and actually decreasing but at a rate that was basically stagnant. Currently, FM1&10 with a gain of -0.1 seems to be working, but I know that this gain has had the damping turn around later so I might damp it till it gets to a low enough level then turn it off.

2025-01-18_05:44:47.588350Z VIOLIN_DAMPING [DAMP_VIOLINS_FULL_POWER.run] timer['shortSleep'] done
2025-01-18_05:44:47.647819Z VIOLIN_DAMPING [DAMP_VIOLINS_FULL_POWER.run] ETMY mode 1 is growing!!  turning off gain
2025-01-18_05:44:47.648013Z VIOLIN_DAMPING [DAMP_VIOLINS_FULL_POWER.run] inUse_mon {'starting_mon': 3.4628171681603113, 'starting_gai
n': 0.1, 'done_damping': False, 'inUse_mon': 3.4628171681603113, 'reset_number': 0, 'guardian_gain': 0.1, 'guardian_damping': True}
2025-01-18_05:44:47.648113Z VIOLIN_DAMPING [DAMP_VIOLINS_FULL_POWER.run] current monitor level 4.462891708360431
2025-01-18_05:44:47.648788Z VIOLIN_DAMPING [DAMP_VIOLINS_FULL_POWER.run] ezca: H1:SUS-ETMY_L2_DAMP_MODE1_GAIN => 0

TITLE: 01/18 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 159Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 6mph Gusts, 4mph 3min avg
    Primary useism: 0.06 μm/s
    Secondary useism: 0.19 μm/s
QUICK SUMMARY: Locked for 25.5 hours. No alarms, but ETMY violin mode 1 seems to be slowly ringing up. I'll start work on damping that. The primary useism seems to have gone up a bit in the last 6 hours, but not the secondary.

TITLE: 01/18 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY: Observing at 157 Mpc and have been Locked for almost 16 hours. Quiet night. I did find the Paging System power cord plugged in - not sure how long it's been plugged in but I unplugged it.

We had a candidate come in earlier (S250118t), and then one just came in a couple of minutes ago (S250118az)!

Our range hasn't been great this evening. I'm not sure why we've been fluctuating so much, but I don't think it's related to squeezing, and the low range diaggui didn't show much. Right now we're back to doing okay range-wise.
 

LOG:

02:32 Superevent candidate S250118t

05:58 Superevent candidate S250118az

Currently Observing at 153 Mpc and have been Locked for 14 hours. Our range has been slowly dropping over the part few hours. Not sure why yet

TITLE: 01/18 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 160Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 7mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.23 μm/s
QUICK SUMMARY:

Observing and have been Locked for over 10 hours. Range dipped a bit earlier due to unknown reasons, but looks to be slowly coming back up.

Closes FAMIS#26354, last checked 82116

** Looking at last 2 weeks since last checked was on 01/04

Corner Station Fans (attachment1)
- All fans are looking normal and within range. There did look to be a period of extra noise following some sort of work done yesterday (Thursday 01/16) on MR FAN1 2, but that looks to have calmed down now.

Outbuilding Fans (attachment2)
- All fans are looking normal and are within range.

E. Goetz, J. Kissel, L. Dartez

Summary:
There is evidence that some of the lines found in the gravitational wave band are actually aliased lines from higher frequencies. So far it is unclear exactly how many of the lines in the run-averaged list are due to this problem and if the lines are stationary or if violin ring-ups may induce more lines in band due to aliasing artifacts. Further investigation is needed, but this investigation suggests that the current level of anti-aliasing is insufficient to suppress the artifacts at high frequency aliasing into the gravitational wave band.

Details:
We used the live, test-point acquisition of the 524 kHz sampled DCPD data in DTT, channel H1:OMC-DCPD_B1_OUT (equivalent to the nominal H1:OMC-DCPD_B0_OUT channel used in loop). This channel had the same 524k-65k and 65k-16k decimation digital AA filtering applied. The time series was exported from DTT and processed by stitching together the time segments into a single time series. Then one can process the time series using the scipy.signal.welch() function of 1) the full 524 kHz sampled data, 2) 524 kHz sampled data decimated (no additional AA filtering) by a factor of 32 to get the 16 kHz sampled frequency data, 3) 524 kHz sampled data decimated using additional AA filtering by using the scipy.signal.decimate() function which has a built-in anti-aliasing filter.

We also plotted in DTT the individual channels against the 16k H1:OMC-DCPD_B_OUT_DQ channel, showing that some of the lines are visible in the in-loop DCPD 16 kHz channel, but not visible in the test point 524 kHz channels.

Figure 1: ASD of raw 524 kHz data (blue), decimated data without any extra anti-aliasing filter applied (orange), and decimated data with additional anti-aliasing filtering (green). Orange peaks are visible above the blue and green traces above ~750 Hz.
Figure 2: ASD ratio of the decimated data without anti-aliasing filtering to the raw data showing the noise artifacts
Figure 3: Zoom of figure 2 near 758 Hz
Figure 4: ASD computed from DTT showing DCPD B Ch 1, 5, 9, 13 and and the H1:OMC-DCPD_B_OUT_DQ channel at the same time as the 9 and 13 channels were acquired (limitations of the front end handling of 524 kHz test points to DTT)
Figure 5: Zoom of figure 4 near 758 Hz

We were also interested in the time-variability of these artifacts and watched the behaviour of H1:OMC-DCPD_B_OUT_DQ, and saw amplitude variations on the order of factors of a few and frequency shifts on the order of 0.1 Hz, at least for the artifacts observed near 758 Hz.

Figures 4 and 5 indicate that there are more artifacts not necessarily directly caused by aliasing; perhaps these are non-linearity artifacts? This needs further study.

A count of the number of 0.125 Hz frequency bins from 0 to 8192 Hz of the ratio between downsampling without additional anti-aliasing filtering and the raw 524 kHz ASD indicates that ~4900 bins are above a threshold of 1.1 (though most of those bins are above 2 kHz, as indicated by figure 2).