TITLE: 09/21 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Very quiet shift, H1 remained locked throughout. Only events of note were a brief drop in observing because of the SQZ PMC and an earthquake passed through.

• 00:51 - Dropped observing from "PMC_REFL_RF35 demod error" in SQZ_PMC Guardian (tagging SQZ)
  • Guardian brought everything back automatically
• 03:15 - Entered EQ mode from M5.6 quake out of Tonga
• 03:54 - Seismic back to CALM

H1 has now been locked for just over 24 hours.

TITLE: 09/20 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:
LOG: The range was in the upper 150s for most of shift, we've been locked for almost 19 hours!                                                                                                                                                                                                                                                       

HAM6 OMC TRANS camera was pretty jittery the whole shift

18:15 UTC, EDC reports 12 DC chans again, from NUC33. The NUC doesn't look frozen as the SQZ plot is still updating.

TITLE: 09/20 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 16mph Gusts, 9mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.10 μm/s
QUICK SUMMARY: H1 has been locked and observing for 18 hours. Sounds like it's been a quiet day.

• Wind and ground motion low
• All other systems nominal

We've been locked for a little over 14 hours, its been a calm day.

The range has been in the high 150s all morning.

The low range check yielded < ~14 Hz SRCL & CHARD_Y (and at >95Hz), and > ~14 Hz PRCL (and at >95Hz) & DHARD_Y coherence.

Fri Sep 20 08:09:52 2024 INFO: Fill completed in 9min 48secs

Closes FAMIS26298

Laser Status:
    NPRO output power is 1.824W (nominal ~2W)
    AMP1 output power is 64.37W (nominal ~70W)
    AMP2 output power is 137.4W (nominal 135-140W)
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 23 days, 21 hr 37 minutes
    Reflected power = 22.08W
    Transmitted power = 104.2W
    PowerSum = 126.3W

FSS:
    It has been locked for 0 days 11 hr and 13 min
    TPD[V] = 0.804V

ISS:
    The diffracted power is around 2.2%
    Last saturation event was 0 days 11 hours and 13 minutes ago

Possible Issues:
    AMP1 power is low, there was a step down about 47 days ago.
    PMC reflected power is high, it appears to have been rising for the past >2 months.

TITLE: 09/20 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 6mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.08 μm/s
QUICK SUMMARY:

• We've been locked for 9:45
• The wind has calmed down, we survived an earthquake 3 hours ago (5.2 from Tonga)

TITLE: 09/20 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: High winds this evening which possibly contributed to the one lockloss. Relocking was automated and otherwise a quiet shift.

• 22:59 - H1 starts observing
• 23:33 - Dropped observing from SQZ PMC unlocking from PZT volts bottoming out (tagging SQZ)
  • Guardian brought everything back automatically
• 23:36 - Resumed observing
• 03:53 - Lockloss - alog80202
• 04:49 - Resumed observing

LOG:

No log for this shift.

Lockloss @ 03:53 UTC - link to lockloss tool

No extremely obvious cause, but seeing as winds have recently gusted up to over 30mph and multiple suspensions seem to have started shaking about a second before the lockloss, my initial assumption is that this was wind-related.

Range had also started dropping for about 30 minutes prior to the lockloss, possibly due to the higher winds? (trend attached)

TITLE: 09/19 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: Three lock losses during my shift. Two of them are unknown. All reacquisitions have been fully auto. SR3 oplev sums are low since the SR3 move last week. Plans to fix this next maintenance day.
LOG:

• 1530 Out of Observing for calibration
• 1600 Starting commissioning
• 1809 Lock loss
  • Full auto, no initial alignment reacquisition
• 1953 Lock loss
  • ALS Y had some odd glitches caused a few lock losses. Tens of minutes later, the polarization of ALS Y and X started to change drastically. This caused the guardian to turn on the controller and adjust it. No idea why the polarization would act like this (screenshot attached). Eventually, after some lock losses at PRMI, everything worked itself out and the IFO made it up. I never touched anything, this was all fully auto without an initial alignment.
• 2201 Lock loss
  • Full auto relock
• 2259 Observing

Samantha Callos, Robert Schofield

We identified 3 peaks (26.4 Hz, 27 Hz, and 29.5 Hz) in DARM resulting from HVAC systems and the CS Chiller; 1 peak between 26.4 Hz and 27 Hz remains unidentified. See Fig. 1.

The first peak at 26.4 Hz's source has been found to be the office HVAC system, as shown in Fig. 2. There are two gaps corresponding to when Robert shut down the HVAC system (from alog 79888). Fig. 3 shows the peak at 26.4 Hz disappears in DARM for when the office HVAC is off vs when it is on.

The second peak varies between 26.5 Hz and ~26.7 Hz. It has yet to be identified, but we do know:

• It has a fundamental harmonic at 13.3 Hz.
• Its strongest, higher harmonics are its 3rd (53.2 Hz) and 6th (133 Hz) harmonic.
• It turns off and on all the time.
• It is seen by both accelerometers and microphones.
• It is seen everywhere.
• Places to look for it next include:
  • LSB
  • LExC
  • Elsewhere?

The third (27 Hz) peak's source is the mini splits HVACs controlled by the downstairs thermostat of the CER, as shown in Fig. 4 when the CER HVAC was shut down (alog 80049). It also shows the second round of shut downs of the office HVAC from alog 79888 which reconfirms the first peak. Fig. 5 shows the peak in the mics disappearing when the "downstairs" bank of the mini splits in the CER were turned off.

The fourth peak's source is the CS main chiller unit, Fig. 6, at 29.5 Hz. This shut down was done by Robert on June 29th, 2024 (alog 78749). A microphone placed across the road from the chiller pads showed that the 29.5 Hz peak seen in the permanent microphones is much louder near the chillers (see Fig. 7).

Finally, in Fig. 8, the coherence between DARM and floor accelerometers is shown for the peaks mentioned above.

FAMIS27798

I ended up not adding any water to either of the chillers since they both looked near the top of their range. The filters looked good, both the mesh and socks. The dixie cup was dry. Sheet updated.

TITLE: 09/19 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 14mph Gusts, 9mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.10 μm/s
QUICK SUMMARY: H1 just made it back to observing minutes before the start of my shift following what sounds like a straightforward reacquisition.

• Wind and ground motion low
• All other systems nominal

The line heights of some of the PCAL lines in the cleaned channel have been much higher than actual at the begining of todays' locks (attachment 1). The relock yesterday didn't have it (attachment 2). Looks like this was potentially fixed a month ago - alog79558, but perhaps the locks from today are too short?

Followed instructions in 74681. Last done in 78782, 79988.  Saved in /ligo/gitcommon/NoiseBudget/aligoNB/aligoNB/H1/couplings/  and pushed to git.

CHARD_P, CHARD_Y, MICH, PRCL, SRCL screenshots attached. The IFO had been in NLN for 4h15 when these were taken. The AS_A_YAW and PRCL offsets were turned off.

Sheila, Louis, Francisco

Following LHO:80044, we measured ASC-DHARD_P(Y) for different ASC-AS_A_DC_YAW_OFFSET and found the loswet values of DHARD_Y at an offset of -0.05.

The "DTT_AS_A_*.png"s show the outputs of DHARD_DARM_240912 when changing AS_A_DC_OFFSET with a reference trace for when the offset was nominal (ASC-AS_A_DC_YAW_OFFSET = -0.15). Each trace has a marker at the two highest peaks in the ASC-DHARD power spectrum (the middle plot on the left). DTT_AS_A_neg0_05 shows the lowest value in the power spectrum compared to DTT_AS_A_neg0_10, while preserving coherence (lowest-left) and phase values (middle-rigt), compared to DTT_AS_A_0. AS_A_NDSCOPE corroborate on the times at which these measurements were done and the values for AS_A offset.

-Mattia, Sheila

We have written a python script to compute the full matrix of power spectral densities and cross-power spectral densities between a given channel, i.e., DARM, and a set of auxiliary channels. The code can be find at this repository https://git.ligo.org/mattia.emma/cross_psd  which includes a README file describing how to run it.

The main arguments the user has to pass are the start time (in GPS time) and length of the data to retrieve from gwpy, a list of channel names and the starting frequency for the strain plots.

The code creates five different types of plots using the coherence and cross-power spectral density matrix. The final result of the code is a coefficient for each frequency value expressing the algebraic sum of the contributions of all the auxiliary channels to DARM considering the cross-power spectral density terms. It also computes the coherence between the single auxiliary channels and the DARM channel, which are the diagonal terms in the cross-power spectral density matrix.

The five kinds of plots are:

1. The cumulative coherence. The sum of the coherence coefficients of the single auxiliary channels with DARM. As we add more and more channels to the sum, one can notice from the plot that the value of the cumulative coherence goes above one, which is unphysical. This motivates the inclusion of the cross-power spectral density terms to account for the correlation between the auxiliary channels.
2. The cumulative strain contribution. Plot of the DARM strain and the iterative contribution of the selected set of channels to the strain. For example 3_<Channel_name> means that the strain contribution was computed using three auxiliary channels and the added channel compared to the previous plot (2_<Channel_name>) is <Channel_name>. This plot has only two lines.
3. Strain_<number>.   Similar to 2 but with as many lines as in <number> plus the DARM strain to show how increasing the number of included channels saturates the DARM strain.
4. Strain_comparison_<channel_name_1>_<channel_name_2>. Similar to 2 but including  the DARM strain and only two lines. One showing the cumulative contribution to the strain until <channel_name_1> and one adding to this <channel_name_2>.
5. Single_coherence_<channel_name>. A plot of the coherence between the DARM channel and the <channel_name>.

All of these plots can also be created using as a main channel any auxiliary channel instead of DARM, e.g., if one would like to study the correlation between auxiliary channels. Each plot name also includes the start and end GPS time of the data used for them.

Comments are welcome. As a next step we would like to implement interactive plots to allow the user to include/exclude lines from the plots.

Vicky, Sheila, Naoki

First we tried SRCL offset of -400, which looked good in yesterday's FIS SRCL offset measurement 79903. We took the calibration measurement with SRCL offset of -400 in 79911, but Louis reported in the mattermost that there is a large optical spring in the sensing function. Also, FDS with SRCL offset of -400 is worse than nominal. Vicky will add more plots for this.

Then we decided to change the SRCL offset to -290 and optimized FC detuning. This improved the sensitivity below 100 Hz as shown in the first attachment and improved the range by ~5Mpc. The optimal FC detuning changed from -34 Hz to -28 Hz and this could be because of SRCL offset change and arm power change.

After FC detuning improvement, we took the calibration measurement with SRCL offset of -290 in 79922, but the measurement did not make sense according to Louis so we took an another calibration measurement with SRCL offset of -290 in 79928.