TITLE: 06/28 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 20mph Gusts, 8mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY:

IFO is in NLN and OBSERVING as of 22:05 UTC

IFO recovered from an ETM glitch lockloss an hour ago.

20:43 UTC lockloss

There was a small ETMX glitch 1/4 of a second before the lockloss

We had been locked for just over 3 hours with a circulating power of ~381 kWs.

BroadBand

Start: 2025-06-28 19:01:05 UTC

Stop: 2025-06-28 19:06:16 UTC

Data: /ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250628T190105Z.xml

Simulines

Start: UTC: 2025-06-28 19:06:42.332738 UTC  // GPStime: 1435172820.332738

Stop: UTC: 2025-06-28 19:30:00.055193 UTC // GPStime: 1435174218.055193

Data:

2025-06-28 19:29:59,859 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250628T190643Z.hdf5
2025-06-28 19:29:59,882 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250628T190643Z.hdf5
2025-06-28 19:29:59,889 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250628T190643Z.hdf5
2025-06-28 19:29:59,897 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250628T190643Z.hdf5
2025-06-28 19:29:59,904 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250628T190643Z.hdf5

Sat Jun 28 10:12:51 2025 INFO: Fill completed in 12min 47secs

TITLE: 06/28 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Aligning
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 5mph Gusts, 3mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY:

• We're in the middle of an alignment
• There's been several medium/large earthquakes overnight
• Low wind, and secondary microseism

TITLE: 06/28 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:

IFO is in ACQUIRE_DRMI_1F and LOCKING

Overall a very calm shift in which we were locked for the majority of it until the ETM glitch (lockloss alog 85402) killed the 8 hour lock.

Relocking was time consuming since the alignment was terrible and we have the 30 min wait before we can do an initial alignment. After I ran a fully auto inital alignment, locking went quickly until we lost lock at LOWNOISE_ASC (522). This also happened yesterday. Just like yesterday, the wind was hovering around 25mph with the primary microseism on the rise. Just like yesterday, there was an earthquake coming through. While I think we could have rode the EQ out and that the wind conditions weren't too bad, I believe that either this state might be a tad more susceptible to such noise or there's a controls issue. (or the same thing happened twice in the same way and will only happen twice). I will investigate tomorrow during shift.

Either way, we lost lock from DRMI but flashes looked good and I think (knock on SSTL) guardian will be able to get into OBSERVING on its own.

On the bright side, we rode through a 6.1 EQ from the phillippines though I did intervene to turn EQ mode on manually since the bulk of the ground motion was starting but the automation hadn't turned it on yet (judging from how much the ISC had to move to keep IFO still).

LOG:

None

Lockloss due to ETM Glitch. H1 Lockloss Tool.

As I was writing this, we lost lock at LOWNOISE_ASC, same as yesterday. There also happened to be a 5.5 EQ passing through (same as yesterday with a more local 3.0 one)

Jennie W, Rahul, Keita

This is just a summary of our work over the last two days trying to repeat the alignment coupling measurements for the replacement ISS array unit (D1101059, unit S1202965). The reason we need to repeat these is because we have now uograded the washer and clamp plate in QPD assembly. See Keita's previous alog for details.

Thursday

First we changed input alignment to get roughly 4 V on each PD in the array, this is acheived by inserting the larger iris and using the two steering mirrors (M2 closest to the array, M1 further towards the laser) to change the input alignment of the auxiliary laser into the unit.

As we have tilted the QPD by adding the new components we need to re-align the QPD to centre the beam (which is split off from the main beam entering the unit by the beam splitter on the elevator assembly which sits at one corner of the ISS array unit).

Then we unscrewed the four screws holding the QPD down (see image) and tried to move the QPD to minimise the coupling from yaw motion if the input beam to pitch. We only managed to minimise pitch coupling and couldn't get it centred on qpd in yaw as the whole QPD unit moves a lot when not screwed down.

We screwed down the QPD but it was still off in yaw by a lot (see image).

As we were adjusting the input alignment mirror to check the coupling I managed to lost the input alignment to the array.

Friday

Today Keita brought the input alignment back by using the beam viewer to check the position on the diodes while changing M2. Then we saw about 3.5-4V on each of the PDs in the array. Next we only undid the two lower screws on the QPD (these hold the QPD unit itself clamped to the platform it sits on, the two upper screws hold in the connector to the back of the QPD and these were only slighly loosened). Keita moved around the unit till the QPD readout showed we were near centred and then we screwed down the unit. It moves alignment while being screwed down probably because of the angle of the QPD relative to the clamp.

For this alignment we used the QPD amplifier unit that gives a live visual readout of the centering.

We also have the option of using another amplifier that gives the QPD X, Y and SUM channels so we can read them on an oscilloscope but these had some weird saw tooth noise on them (see image from Thursday). Keita then discovered that we were using the wrong cable (too low a current rating) for this amplifier, we searched for the correct one but could not find it. We will get back to this on Monday.

Summary: We think we now have the QPD in a good place relative to the PD array as yaw and pitch are fairly decoupled, but maybe the angle of the QPD in rotation is still slightly off as the P and Y motion of the beam are still slightly off from the QPD quadrants. We need a new cable for the ON-TRAK amplifier.

M. Todd, S. Dwyer

This morning we made a change to the thermalization guardian (managed by ISC) with flags that allow the SQZ guardian to turn on the SQZ_ASC in the unthermalized state or this guardian can turn on SQZ_ASC after 75 minutes (thermalized-ish). We also turned the monitoring off so that this switch does not knock out observing.

For more info see:

TITLE: 06/27 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: We've been locked for just under 5 hours, calm day.
LOG:

• The LOCKLOSS_SHUTTER_CHECK failed at 09:05 UTC, I've added a check in H1_MANAGER to specifically look for the SHUTTER_FAIL state.
• 17:02 UTC lockloss
  • 18:25 UTC I adjusted the OPO temperature while relocking
  • The FC struggled to lock IR and we ended up changing the threshold
  • 19:33 UTC Observing
    • 19:43 UTC We dropped observing for <1min as the SQZ ASC turned on and threw out an SDF diff which I unmonitored

TITLE: 06/27 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 14mph Gusts, 9mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.05 μm/s
QUICK SUMMARY:

IFO is in NLN (since 18:36 UTC) and OBSERVING since 19:33 UTC (4.5 hr lock)

An hour was spent comissioning to fix SQZ ASC, which now runs deeper into thermalization after NLN.

Otherwise, just planning to continue observing as long as possible!

Closes FAMIS 26399. Last checked in alog 85208.

All fans nominal, comparable to last week and within threshold.

Closes FAMIS 26456. Last checked in alog 84705

Trends look normal. SEI BRS Maintenance work in Mid-May was part of vent work and is the only excursion from the threshold lines.

J. Kissel, F. Clara
ECR E2400330

Fil modified another UK SatAmp (D0900900 / D0901284) per ECR E2400330, which means "rev'ing" up the D0901284 circuit board inside from -v4 to -v5.

However, this one, S1000278, seems to have more variability in components that were not changed between channels -- namely if I 
    - fit the measured zero and pole frequency, and 
    - assume that a perfect, as drawn, value for the R181 = R182 resistors (as Fil confirms that these were +/-0.1% resistors)
the total capacitance seems to have a ~2% variability. 

Not unreasonable, given that typical off-the-shelf caps of value 10 [uF] have +/-10% variability, so with two of these caps parallel, you could expect the total capacitance to be between 18 and 22 [uF], or +/-10%.

As such, I propose we set a tolerance for these transfer functions to have the following values at the following "check" frequencies (i.e. logspace(log10(5),log10(50),3), which is a requestable frequency vector on an SR785 frequency response sweep, if fstart = 50, and fstop = 0.5, with N points = 3). These assume values assume 1% variation in transimpedance amp feedback resistor, and 2.5% variation in whitening cap.

    Freq    Mag (Upper Bound)    Mag (Lower Bound)    Phase (Upper Bound)   Phase (Lower Bound)  
    [Hz]    [V/V] or dB([V/V])  [V/V] or dB([V/V])          [deg]               [deg]

    0.5      5.4098 or 14.664       5.0554 or 14.075      -106.23             -106.5

    5.0     38.415  or 31.69       36.671  or 31.286      -135.09             -133.72

    50.     54.987  or 34.805      53.868  or 34.627      -174.2              -173.9

    Freq    Mag Tolerance              db(Mag Tolerance)          Phase Tolerance 
    [Hz]    [V/V] +/- [V/V]         dB([V/V]) +/- dB([V/V])     [deg]  +/-   [deg]

    0.5      5.2313 +/- 0.17847       14.372 +/- 0.29138      -106.36  +/-  0.12754

    5.0     37.547  +/- 0.86844       31.491 +/- 0.19861      -134.41  +/-  0.67952

    50.     54.428  +/- 0.55902       34.716 +/- 0.088757     -174.05  +/-  0.14395

That being said, we wouldn't replace the non-ECR components if the SatAmp didn't pass this test, we'll just use those under-performing SatAmps to be used on low priority stages, i.e. ones not used for damping loop control, i.e. not top mass stages. If many end up exceeding this thresholds, then we can start to prioritize which suspensions get the best.

Fri Jun 27 10:12:24 2025 INFO: Fill completed in 12min 21secs

The filter cavity was having a hard time locking, and it looks like the FC green trans power has been dropping slowly over the last 3 weeks, which seems to be caused by a drop in the SHG power from around 100-110 mW down to 77 mW . 

I adjusted the picos and the SHG temperature, and recovered the SHG power to 86 mW, so there is still a lot of missing power.  The filter cavity locked after this.

I've added a template for this adjustment to userapps/sqz/h1/Templates/ndscope/SHG_alignment_temp_adjust.yaml

Lockloss at 17:02 UTC in NLN while we were waiting for the FC to lock.

TITLE: 06/27 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 9mph Gusts, 4mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.05 μm/s
QUICK SUMMARY:

• We were stuck in PREP_FOR_LOCKING with ISC_LOCK stalled with IFO_NOTIFY and H1_MANAGER asking for help (10:22 UTC)
• As soon as I requested H1_MANAGER back to idle it released ISC_LOCK and we started to lock again
  • At first glance I'm not sure why it was stuck
  • The timer "to NLN with an initial alignment already having run" was why it was calling for help but it should have kept trying to lock itself?