Matt, Camilla

After TJ and Dave fixed the HWS Live GUI 87252, Matt and I checked on it and re-centered the origin crosses which are meant to mark the center of where the IFO beam is heating the ITM, before and after, sdf diff. We moved them both down but we hadn't updated them in a few years so this isn't too surprising. 

Also attached is a HWS image of the test masses comparing getting to 60W in to 180s later, plot. As usual, ITMY looks clean and ITMX has it's known point absorbers. There is some edge effects on ITMX that should be ignored.

TITLE: 10/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 12mph Gusts, 8mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.41 μm/s 
QUICK SUMMARY: Looks like we lost lock 2 hours ago. An initial alignment was done an hour ago, but DRMI is not catching despite high flashes. 

Planned calibration and commissioning today, but we need to get back up first.

TITLE: 10/01 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY:

H1 has been locked over 18hrs with no issues this shift.

I took some more histograms of our locking sequences today.
ALS
DRMI-BiWeekly
DRMI-Monthly
DRMI-Daily Average 
Carm
Powerup
& NLN
 

Checking in on our DARM lockloss status after the second month of having our higher bias. At the end of August I put some comparison plots in to show how the doubling of the bias had significantly decreased the number of locklosses we had, as well as also significantly decreasing the amount of those locklosses that were due to the DARM glitch(86678). I remade those plots again now that we've gone through September.

In my usual lockloss vs DARM lockloss plot, we see that we've actually had no locklosses due to the DARM glitch between September 3rd - September 30th, which is the longest we've gone in all of O4 without that lockloss cause!

The average lock length has gone down a bit compared to August (10.8 vs 13.3 hours), but that's still double the average lock length of February, March, June, and July (table, plot). The number of lockloses is still also much lower than the pre-ESD-doubling months.

TITLE: 10/01 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 8mph Gusts, 5mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.59 μm/s 
QUICK SUMMARY:

H1's been locked 12.5+hrs, even with microseism a little higher than last night! Cloudy skies, light breezes and an Operator BBQ celebrating O4a & Detections operators were on-shift for.

TITLE: 10/01 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Locked for 12 hours. The useism is staying constant, wind is staying low. 
LOG:

• 1418 GRB short E606087
• 1431 GRB short E606088
• 2137 GRB short E606216

We recently noticed that the HWS live GUI wasn't working. In trying to troubleshoot this, I found that there are a few different instances of it - gitcommon area, userapps, personal alias's, and maybe others that I dont know about. They were either copies of the git code, pointed at different branches of the git repo, or modified versions, but none were consistent. I've now corrected the new path for the hws data directory (alog84865), and updated the git repo with the changes. The version in userapps I've just copied from this for now so it continues to work, but I'd like to change that in the future. 

Long story short, it should work now.

Locked for 8.5 hours. The useism is still >90th percentile and our SEI_ENV node is in USEISM as a result. Range is stable.

FAMIS 31105

Looks like most things have settled out after our table inspection last Tuesday (alog87143), although PMC reflected power has been moving around a bit more than usual. ISS diffracted power also has been falling slightly, but right now it looks to have settled at around our target of 4%.

Wed Oct 01 10:07:13 2025 INFO: Fill completed in 7min 9secs

Looked at the last 6 locklosses from Observing. 

Could see nothing much in all but one of them, 1443315128 where ETMX_L3 and DARM get noisy in the 70ms before LL, plot attached. 

TITLE: 10/01 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: SEISMON_ALERT_USEISM
    Wind: 10mph Gusts, 7mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.51 μm/s 
QUICK SUMMARY: Locked for 3.5 hours. Two GRB shorts passed through, E606087 and E606088 at 1418 and1431UTC. No alarms. The useism is just getting above the 90 percentile.

Plans for today...Observe!

H1 Manager woke me up complaining about having been out of Observing for over 10 minutes. I checked and found that the issue was that the OPO ISS was not able to stay locked. I took the detector to NO_SQZING, took the OPO guardian to LOCKED_CLF_DUAL_NO_ISS and noted that OPO trans was around 62 uW, much lower than our 80 uW setpoint, so I used 86767 as a checklist of what to do, since we had had the same issue a few weeks ago.

I checked the SHG temp (it had been updated earlier today (87233), and it was still looking good and above 90mW, so I went to the next step from that alog - adjusting the half wave plate that's in the SHG path between the 200 MHz AOM and the SHG Rejected Power PD. I had an ndscope open with H1:SQZ-OPO_TRANS_LF_OUTPUT and H1:SQZ-SHG_LAUNCH_DC_POWERMON, and adjusted the wave plate a step at a time until the SHG launch power was about/above what it had been before (~26uW), and OPO trans was above the 80 uW setpoint. Once that was done, I was able to relock and reinject squeezing with no issues and went back into Observing.

TITLE: 09/30 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:

Locking was not trivial (seems like first time in many weeks for me).  Wish I could say I solved the issue, but really all I did was run a 2nd alignment and then let H1 lock.
LOG:

• 0051 Lockloss
  • Both X & Y green arms ran Scan Alignment
  • Then X-arm needed a 2nd one as its nice alignment was driven off by ASC, but then it was fine for this 3rd attempt.
  • Ended up going to CHECK_MFs + PRMI because DRMI was not having it.
    • During DRMI, moved BS in pitch a bit (but when trying to find where I started via ndscope, I had trouble seeing that trend data).  20min later I ran a Time Machine and saw that I steered the BS off a bit.  So, after restoring it, I went for a 2nd round CHECK_MFs + PRMI.  I wish ndscope wouldn't freeze like this. 
  • Ran Alignment---everything looked good, but DRMI & PRMI would not lock.
  • Was contemplating calling for help, but decided to run a 2nd alignment....and then I left the Control Room to work on the JAC table and allow h1 to lock without me watching it!  When I came back after about 20-30min, H1 had locked DRMI and was on its way to NLN
• 0405 OBSERVING

H1 had a lockloss about 90min ago for no obvious reasons.  All was quiet as well.  Attempted to relock but DRMI did not look great; also went for Check MICH Fringes + PRMI---could not even get PRMI locks after letting it try for 20min.  Ultimately went for an alignment and where we are.  Flashes look mostly decent and POP18/90 are flashing close to 200, but just have not had any locks (only a few short ~1sec locks thus far).  Microseism is just under the 95th percentile.  Currently at 20min of DRMI locking.

M. Todd

Summary

This morning I used the early maintenance day to come in and make some measurements of IMC DOF Transfer Functions to ISS Second Loop RIN. I started by doing some OPS/GRD settings as I was here about an hour before the operator was set to come in.

I got through the first DOF measurement (DOF_1_P) without any hiccups; however a 7.0 earthquake from Philippines came in an unlocked us. Fortunately, I did not have to wait long for the IMC to relock and I proceeded with the other measurements.

DOF 1 and DOF 2 are relatively robust, but upon starting the DOF 3 measurement I had to lower the gain even more than anticipated, as the 1 and 3 Hz resonances are quite strong. The first run at this unlocked the IMC. After clearing the IMC DOF 3 P history, I let the IMC relock (it was having trouble) and continued with the subdued measurements.

I also tried to measure the UGF of each DOF loop, but was nervous about injecting that hard at the frequencies I suspected would contain the UGF.

Later, I will post a comment that tries to map the quiet time IMC contributions to the ISS Outer RIN in the regions we have enough coherence.

List of Figures

1. DOF 1 P Measurement of IMC to ISS 2ND LOOP RIN
2. DOF 1 Y Measurement of IMC to ISS 2ND LOOP RIN 
3. DOF 2 P Measurement of IMC to ISS 2ND LOOP RIN
4. DOF 2 Y Measurement of IMC to ISS 2ND LOOP RIN
5. DOF 3 P Measurement of IMC to ISS 2ND LOOP RIN
6. DOF 3 Y Measurement of IMC to ISS 2ND LOOP RIN

Since maintenance will start early next Tuesday, I've updated the PEM_MAG_INJ node to start its injections at 6:00am (13:00 UTC) and the SUS_CHARGE node will start at 6:25am (13:25 UTC). These should all be finished by 6:45am (13:45 UTC).

During Tuesday maintenance, we swapped the HAM6 AIP (Starcell). Note this annulus system is connected to HAM5 via the septum plate. We vented the lines with dry nitrogen and left a continuous nitrogen purge(~.3 psi) of the line during the pump swap. Nitrogen attached to HAM5 pump out port while HAM6 pump out port was left open to atmosphere.

No issues during the swap, annulus system is now pumping at both HAM5 & 6 ports with an aux cart and turbo pair. As of end of maintenance, the HAM6 cart was at ~3E-5 Torr, HAM5 cart at ~1E-4 Torr. These pumps will continue running until pressure is <1E-5 Torr at which point the ion pumps will be powered on.

Carts are placed on foam for isolation, and a piece of foam between the flex hose running up to HAM6 pump out port and HAM6 chamber. See attached pictures. 

Work permit will be closed once pumps are disconnected from chambers.