TITLE: 06/17 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 134Mpc
SHIFT SUMMARY:

- Lock #1:

• Arrived with H1 locked and in observing as of 4:59
• Lockloss @ 9:10

- Lock #2:

• Y arm struggled a lot relocking, INCREASE_FLASHES ran twice and got flashes to 0.9 but still took awhile for it to finally catch
• Went through PRMI which caught quickly and DRMI locked afterwards
• Acquired NLN @ 10:31, OBSERVE @ 10:39
• 10:33 - 5.5 EQ from Taiwan, hopefully we will be able to ride it out - success!
• 11:20 - SEI to CALM on verbal alarms when there was no indication that it ever transitioned out in the first place?
• 11:49 - another EQ...6.0 from Tonga, EQ mode activated @ 11:50
• 11:52 - potential aftershock from the previous EQ, not looking great...with ground motion ~ 0.7 um/s, SEI still went back to CALM then back to EQ shortly after - Tagging SEI
• Lockloss @ 13:23

- Lock #3:

• Locking was entirely automated
• Acquired NLN @ 14:21, OBSERVE @ 14:30
• EX saturation @ 14:39
• PI 31 ringup @ 14:44, guardian damped the mode automatically

- A good chunk of the night was a wash due to multiple EQs, high wind speeds, and slow lock reaquisitions, leaving H1 to Ryan S. in observing, hopefully seismic actiivity will taper down soon

LOG:

No log for this shift.

LOCKLOSS @ 13:23, not seeing a whole lot of ASC motion, but am seeing a bit in the LSC loops. Can probably rule out the earthquakes since ground motion has been on the decline. Wind speeds however are getting fairly high, hovering around 30 mph.

I have trended the top mass OSEM inmon channels, the optic align offsets, and the FMCS temps for zone 1A and zone 5, both over short term (~3 weeks, around the start of the excursion), and over a couple of months. From looking at the plots over the long term and after recovery, most OSEM and optic align readouts are relatively where they were before the excursion EXCEPT for DAMP_P_INMON and DAMP_V_INMON. Looking at the scopes, the DAMP_P was ~ -650 counts before the excursion and is now hovering around -640. DAMP_V seems to have had the biggest change, coming from ~32 before the excursion to roughly 50 today. In principal, this makes sense, since temperature swings mostly affects suspensions in the vertical direction, P and V. This is direct evidence that the OSEM vertical sensors are definitely not in the alignment they were before, but the rest for the most part have been restored to their original values.

Following a lockloss, H1 is now relocked and in observing as of 10:39 UTC. A 5.5 magnitude earthquake from Taiwan is currently rolling in, though ground motion has been relatively low so far.

LOCKLOSS @ 9:10, looks like a potential LSC PRCL ringup. Wind is also on the rise.

TITLE: 06/16 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
SHIFT SUMMARY:

Decent shift with no EQs which knocked us out (appeared to ride through a Japan and Panama EQ), but an EY wind probably caused a lockloss (the other one most likely from a HAM1 ASC FF filter change).  Reacquisition was fairly good (except during the 90-min wind storm.

LOCK#1: (2335-2357) After a very short OBSERVING segment

• Xarm green needed INCREASE FLASHES
• LOCKLOSS at OFFLOAD DRMI
• During this lock I was backing out the HAM1 ASC FF changes.

LOCK#2:  (2358-0056)

• 0050 Verbal says we are at NLN, but....(orange)
• 0056 Camera Servo completes & green NLN
• 0057 OBSERVING

LOCK#3: (0339-0459)

• This occurred during a 90min pick up of wind (mainly at EY), but interestingly, X-arm green had trouble relocking.
• To speed getting back to Observing, I went directly to PRMI.  Then ISC_LOCK did the rest.

LOG:

• 2317-2326 Elenna running a measurement/test while H1 is hanging out in the OMC_WHITENING state waiting for violins to calm down after the EQs (almost to NLN).  She ACCEPTED some SEI_PROC SDF changes for HAM1 Feed Forward.
• 2328 Back to OBSERVING!
  • 2334 And then a lockloss (which had a 90min ring up of ASC's MICH_P).
• 0043 Incoming EQ notification received on Verbal (Hokkaido M5.6)
  • 0046 Start to see EQ on picket fence and 0.03-0.1Hz BLRMS.
• 0057 Back to OBSERVING
• 0110-0142 Stopping and picking up pump from MY and bringing back to CS Mechanical Room (Janos)
• 0139 Run down Xarm (Brice)
• 0336 LOCKLOSS
• 0330-0525 Winds w/ peaks above 30mph (w/ EY highest)
• 0459 OBSERVING
• 0542 PIMode 31 alert, but was automatically handled.

TITLE: 06/17 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 132Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 15mph Gusts, 10mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.14 μm/s
QUICK SUMMARY:

- H1 has been locked an in observing as of 4:59

- CDS/DMs ok

- SEI motion a little elevated due to previous EQs but looks to have stabilized

After initial locking work, H1's been nicely locked for 2.25+hrs with a range just under 135Mpc.  Breezes picked up a little earlier, but have been stable.  With the long weekend, I went and shut off alot of the lights around the OSB & Mechanical Room.

(Corey, Elenna)

With our short OBSERVING stretch (6-min) ending due to a ringing-up (over 90-sec) ASC MICH_P (see attached), Elenna and I decided to back out her HAM ASC FF change for this recent lock. 

Elenna's change was:

• at SEI -> ISI Sensor Config -> HAM1 ASC FF -> ASC P (from pull-down),
• for the (4) INP1 & (4) PRC2 filter banks (see attached showing some of the windows involved)
• with the filter change for the FM4 filter ("FFX0616")

We have now reverted from this new FM4 to the original FM3 ("FFX0423").

TITLE: 06/16 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
SHIFT SUMMARY: Shift was full of earthquakes, keeping us down for several hours.

Lock #1:

• Dropped Observing from 16:08 to 16:44 for calibration measurements: alog 70520
• Lockloss @ 16:54: alog 70521

Lock #2:

• 4.9 earthquake from France, lost lock while acquiring DRMI
• Relocking went unaided; NLN @ 18:29
• Lockloss @ 18:40 (before Observing) from backscatter test at HAM3: alog 70528

Lock #3:

• Lost lock at TURN_ON_BS_STAGE_2

Lock #4:

• Made it to MOVE_SPOTS before a 6.5 quake from Tonga hit, holding in DOWN until it passes

Lock #5:

• Finally was able to lock after ground motion calmed down
• Relocking is going unaided (needed to CHECK_MICH_FRINGES and PRMI)

Handing off to Corey, H1 currently at MAX_POWER.

LOG:

TITLE: 06/16 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Earthquake
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 18mph Gusts, 14mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY:

Arrived to see h1 working on getting back to NOMINAL LOW NOISE due to a big earthquake.

HAM6 OMC camera is still not on nuc30.

It's a little windy, but still better than earlier this week!

I have found a couple cases lately where SEI_ENV was switching out of earthquake mode too quickly. Peakmon was still around 1000nm/s, fairly high, and SEI_ENV would switch back to the nominal state. During the winter, I had to increase this transition threshold from 600 to 1100 because the high microseism was fooling the SEI_ENV guardian. After that, I made an adjustment to the bandpass filter peakmon uses, to better filter out the microseism (here), but didn't reassess the SEI_ENV thresholds. I've set it back to 600 for now, I'll try to figure out if we can live with this threshold wrt the filter I installed in January.

This shouldn't really affect my alog about the earthquake robustness. This threshold affects the transition out of the earthquake mode, there is a separate threshold of 400nm/s for the transition into the eq mode with seismon early notifications, and we are mostly losing lock before even reaching that threshold.

J. Kissel

For quick reference -- the current HAM-ISI blend filters are:
    (X, Y, Z) are all using the "comp_250" blend filter pair, whose blend frequency is 0.18 Hz (or 180 mHz -- hilariously *not* 250 mHz...)
    (RX, RY) are both using the "many_notches" blend pair, whose blend frequency is 0.375 mHz
    (RZ) is using the "fc_yaw_filt_lp." 

The recent ECR E2200473 that improves the performance of switching between blend filters also completely revamped the naming scheme for the filter banks which house the blend filters. That means older, extremely useful code like 
    /ligo/svncommon/SeiSVN/seismic/Common/MatlabTools/plot_current_blends.m
which converts the "as installed" foton representation of the blend filters into their design-intent, dimensionless "complementary" form broke.

Not having that code forced the infrequent viewer / non-designer to cut corners and only look at the displacement sensor blend, and either waive their hands guessing at the blend frequency / frequency-shaping or invent their own metric for "at what frequency do we start to get inertial isolation," e.g. as in LHO:70313.

I've now fixed the above mentioned code for the HAMs -- see attached collection of plots which show the 4 pairs of blend filters which are in play on ALL HAM ISIs at LHO (ISI HAMs 2 - 8).

Along the way, I couldn't help myself but to improve the plots:
    (1) I've added an explicit indication of the the blend frequency,
    (2) tightened up the frequency range and magnitude limits so you can quantitatively read off the magnitude better
    (3) For the phase, we used to plot both the individual filter's phase and the sum, but really only the sum matters. The sum of the HP and LP pair's deviation from 1.0 magnitude and 0.0 phase is a metric for *lack* of complementarity, and thus 
        (a) how much the open loop gain shape is impacted for *this* pair of filters and 
        (b) how much the phase will *change* when we switch to another set of blends with different [lack of] complementarity)

The code still needs further updates to handle BSC-ISI ST1 sensor blends, but I leave that for another day, or the initiative-full reader.

Lockloss @ 18:40 UTC from placing the retro-reflector into a viewport on HAM3 for a backscatter test.

Here is a list of the things we need to change to return as closely as possible to a desirable 60W configuration.

• Ring heaters: 1W ring heater power on both ETMX and ETMY. No change to the current ITM ring heater settings because we are running at the same settings as 60W
• CO2 settings: 1.7W annular on both ITMX and ITMY (we are currently running with these settings). Depending on the amount of time we have to do TCS additional commissioning, it might be worth some time to see if we can improve frequency noise by changing these settings differentially (increase CO2X power). See this alog comment for more details: alog 68842
• OM2 TSAMS: no change
• ASC, control design: I don't believe we need to make any changes to the loops. There has been significant update to the recycling cavity loop design at 76W, but these are power independent. The HARD loops are running with loop compensators designed for about 400 kW of power. I think dropping to 380 kW should not negatively impact the loops, as the hard loops have been stable through thermalization which can change the arm power by 30 kW. The soft loop compensator design is the same. We may even be able to reduce some soft loops gains, as most of the soft loop gains were increased to compensate for the 430 kW operation.
• ASC, HAM1 FF: pending another 5-10 minute on/off test to collect data, we can either use the current filters, or revert to ones that I tuned on April 6 while at 60W. See alog. The filters are named by the date they were installed (so just turn on the ones labeled 0406). We did not need HAM1 FF in the yaw loops at 60W, so we can turn off all those filters first and then check the necessity again.
• LSC, control design: we should consider reverting the PRCL control loop design. Gabriele designed a new loop that could manage the gain loss at 430 kW in addition to adjusting the loop gains. We will likely still need to adjust the PRCL loop gain throughout the lock at 60W. Once we go down in power we should dedicate some commissioning time to determine the gain loss trend and commission accordingly. We should also check that the UGF of MICH and SRCL are where we expect them to be. The PRCL1 filters are FM2, 3, 4, 5, and 6 with a gain of 11.6 and none of the PRCL2 filters were in use.
• LSC, feedforward: we will need to tune the LSC feedforward. We had been running with an outdated LSC feedforward with the plan to remeasure and update it once we settled on a final configuration. All recent updates occurred at 76W. The filter for SRCL was FM2, labelled EDH used with a gain of 1. The filters for MICH were FMs6-9, however FM9 has been overwritten by a new filter. I will use the archive to recover it. The MICH filters used a gain of 0.97.
• CARM gain: the CARM gain was increase by 3 dB to counteract the loss of gain that occurred during thermalization. We should remeasure CARM and determine if we still need that gain increase. alog 69152
• ISS second loop gain: we reduced the ISS second loop gain to -5 dB. We should remeasure the loop and determine a better gain setting for 60W. alog 68789
• SRCL offset: we had been running with an offset of -175. This was also with the previous LSC-POP_RF45 whitening at 21 dB. We could revert the whitening change as well if we think it's better for noise considerations
• DARM offset: 20 mA, not sure if we want to revert this value

If you are looking for a timestamp to determine when the power change occurred, the last full lock at 60W was on April 6 from about 17:00 UTC to April 7 3:30 UTC.

Commissioning period,

The Ham1 FF was turned off for testing on 06/14/23 21:32:15. It stayed off for 5 minutes and was turned back on at 21:37:15.

The previous timing master which was again running out of range on the voltage to the OCXO, see alog 61988, has been retuned using the mechanical adjustment of the OCXO.

Today's readback voltage is at +3.05V. We will keep it running over the next few months to see, if it eventually settles.