For the SR3 P estimator, we had initially developed and installed blend filters (in H1:SUS-SR3_M1_EST_P_FUSION_MEAS_BP and H1:SUS-SR3_M1_EST_P_FUSION_MODL_BP filter banks), named pit_v1, that blended between the OSEMs on-resonance, and the estimator everywhere else (86452). After a bit, Brian Lantz made a pit_v2 that included OSEM damping at two extra frequencies because we were having issues with extra resonances at 0.65 and 0.75 Hz that weren't being damped (86510)(filter comparisons).
Eventually we realized the reason why those two peaks weren't being damped was because we had forgotten to include the model contribution to P from L, and we installed those needed filters(86567). However, we didn't swap the blend filters back to pit_v1 at the time.
So during relocking today (2025/10/13 19:05:00 UTC), I swapped us back to pit_v1. We will run with this until at least tomorrow morning and then verify that we don't see a difference in the damping of those two peaks.
Oli - Thanks for doing this test, I'm looking forward to learning what happens. I think the question here is "how well does it work" and "what do we see" rather than "does it work". I'm hoping this will reduce the RMS a bit, although the analysis is complicated by the cross-coupling w/ length.
Lock loss 1444412849
While it was during commissioning, it seems like it wasn't any of the activities going on at the time. Looks very much like the most recent lock losses we have that very quickly go.
Back to observing at 1917 UTC. Ran initial alignment, but I didn't have to do anything.
Jennie W, Elenna
Today we changed the OFI temperature and monitored the OFI PD A power. At each temperature change, we reran Sheila's OMC fringe wrapping injection to replicate the measurement Sheila and Naoki did in alog 78942.
Results: we did not see a very significant change in the OFI PD A power when we changed the OFI temperature from 37.5 C to 25.5 C. We see a smaller scattering shelf at 25.5 C than we do at 37.5 C.
I saved Sheila's template over into my own directory as /ligo/home/elenna.capote/OFI/OMC_fringe_wrapping.xml
She had old references in that template (different from the alog) that were taken in Sept 2024. Those references indicated that an OFI temperature of 37.5 C had the smallest scattering shelf. Today, Jennie and I saw very little difference between the scattering shelves generated at 37.5 C (nominal temperature), 34.5 C and 30.5 C. Only when we measured at 25.5 C did we see the scatter shelf reduce slightly (plot).
In this plot, I added in Sheila's old references that show the exact opposite result a year ago. Specifically, the 25.5 C measurement from now is very close to the old 37.5 C measurement from a year ago.
At first, I didn't think there was much of a change in the power on OFI PD A. However, looking at the second trend, it looks like maybe the power dropped by a small amount. I might have needed to slow down this test more than I realized (plot). I saved this ndscope template in /ligo/home/elenna.capote/OFI/OFI_TEC.yaml
Mon Oct 13 10:07:35 2025 INFO: Fill completed in 7min 32secs
FAMIS 31107
The main changes that can be seen this week are a result of our amplifier pump diode current adjustments on Tuesday (alog87338). Otherwise, no major events this week.
TITLE: 10/13 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 17mph Gusts, 12mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.22 μm/s
QUICK SUMMARY: Locked for 21.5 hours. No alarms, two GRB shorts overnight.
TITLE: 10/13 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:
IFO is in NLN and OBSERVING (12 hr lock)
We were locked for the entirety of shift.
The range came back over the course of the shiftso did not have to leave OBSERVING to touch up the squeezer.
Wind and ground motion look good
LOG:
TITLE: 10/12 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: One lock loss that only needed initial alignment but full auto. After we thermalized I ran a calibration sweep in coordination with LLO. The range for this most recent lock looks to be trending down slightly. The SQZ blrms see it, but Ibrahim will keep an eye on things.
LOG:
TITLE: 10/12 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 27mph Gusts, 21mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.22 μm/s
QUICK SUMMARY:
IFO is in NLN and OBSERVING (6 hr lock).
Range is slowly going down seemingly due to SQZ. Wind is also picking up. If range continues to degrade, will re-tune the squeezer.
FAMIS27825
No water added, values all looked good and were recorded into the sheet T2200289 sheet.
I somehow missed this and its a week late, next one should run next week.
Coordinated a calibration measurement with LLO since we couldn't get it done yesterday. Back into observing 2029UTC
Simulines start:
PDT: 2025-10-12 13:04:59.811759 PDT
UTC: 2025-10-12 20:04:59.811759 UTC
GPS: 1444334717.811759
Simulines end:
PDT: 2025-10-12 13:28:25.449920 PDT
UTC: 2025-10-12 20:28:25.449920 UTC
GPS: 1444336123.449920
Files:
2025-10-12 20:28:25,294 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_
SS/DARMOLG_SS_20251012T200500Z.hdf5
2025-10-12 20:28:25,302 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DA
RM_SS/PCALY2DARM_SS_20251012T200500Z.hdf5
2025-10-12 20:28:25,308 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_
L1_SS/SUSETMX_L1_SS_20251012T200500Z.hdf5
2025-10-12 20:28:25,312 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_
L2_SS/SUSETMX_L2_SS_20251012T200500Z.hdf5
2025-10-12 20:28:25,317 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_
L3_SS/SUSETMX_L3_SS_20251012T200500Z.hdf5
Sun Oct 12 10:08:26 2025 INFO: Fill completed in 8min 22secs
We've recently been having some issues with SRM tripping during initial alignment and during DRMI acquisition, alog87370 for example. After consulting with Jeff K, I've bumped up the trip thresholds as listed below. This was based off of the last few trips, so hopefully it has enough of a buffer now. Saved in the safe and observe sdfs.
| Old | New | |
| M1 | 150 | 250 |
| M2 | 200 | 350 |
| M3 | 225 | 400 |
Lock loss 1444317365
No obvious cause, ended a 29.5hour lock.
1659 Observing. Needed an initial alignment, but all auto.
TITLE: 10/12 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 9mph Gusts, 5mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.28 μm/s
QUICK SUMMARY: Locked for 28.7 hours, range is stable, no alarms, no alerts overnight.
TITLE: 10/12 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:
IFO is in NLN and OBSERVING (19 hr lock!)
Range is stable. Environment is stable. Locked for the whole shift.
LOG:
None
TITLE: 10/11 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 15mph Gusts, 8mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.20 μm/s
QUICK SUMMARY:
IFO is in NLN and OBSERVING
Calibration sweep was not run this morning due to LLO not being thermalized. TJ plans on running it tomorrow with LLO.
Otherwise, LHO has been quietyl observing for ~14 hours!
Today I began calibrating the camera servo signals into spot positions. I ran the A2L script at the nominal camera spot positions. Then, I changed the camera offset and waited for the camera servo to converge. Then I remeasured the A2L gain. Using the a2l_lookup function in /opt/rtcds/userapps/release/isc/common/scripts/decoup/BeamPosition the A2L gain can be converted into a spot position in mm. This is a slow process so it will take time to get the conversions for all.
| Camera offset | A2L gain | Conversion | |
| ETMY Pitch | start: -230, end: -231 | start: 5.62, end: 5.92 |
(-23.2 mm - -21.8 mm)/-1ct = 1.4 mm/ct |
| ITMX Pitch | start: -230, end: -231 | start: -0.45, end: -0.56 |
(6.46 mm - 5.96 mm)/-1ct = -0.5 mm/ct |
I continued today following the same process stated above.
| Camera offset | A2L gain | Conversion | |
| ETMX P | start: -173, end: -172 | start: 3.04, end: 2.92 |
(-9.38 mm - -9.93 mm)/ 1ct = 0.55 mm/ct |
| ETMY Y | start: -349.5, end: -348.5 | start: 1.41, end: 1.06 |
(3.90 mm - 5.18 mm) / 1ct = -1.28 mm/ct |
| ETMX Y | start: -422, end: -421 | start: 4.85, end: 4.68 |
(17.22 mm - 17.84 mm) = -0.62 mm/ct |
I reran the ITMX beam spot calibration following the same method described above, but this time I checked how the beam spot moved on both ITMX and ITMY when I changed the BS camera offset. Turns out, they give the same answer, so that's good.
| Camera Offset | A2L gain | Conversion | |
| ITMX P (ITMY P) | start: -230 ct, end: -231 ct | start: -0.45 (0.19), end: -0.55 (0.09) |
(6.41 mm - 5.96 mm)/-1 ct = -0.45 mm/ct |
| ITMX Y (ITMY Y) | start: -236 ct, end: -237 ct | start: 3.18 (-2.75), end: 3.06 (-2.63) |
(11.26 mm - 11.70 mm)/ -1ct = 0.44 mm/ct (-0.44 mm/ct for ITMY) |