[Corey, Jenne]

Corey was struggling with the MICH_BRIGHT step of initial alignment.  He let me know that the guardian kept looping through that set of states, and that MICH wouldn't lock.

Things in general looked fine (as in, the past things that have been struggles with this state), so I started looking at the MICH error signal.  It didn't look fine, even though the beam was reasonably well centered on the AS_A WFS diode.  There were PDH-looking jumps in the error signal, when we expect a MICH-only error signal to be a nice smooth signal.  That pointed me toward looking at the misalignment of various optics (PRM, SRM, ETMs), at which point I noticed that the OFFSET values for the TEST filter banks on the ETMs were zero rather than the ~10urad we normally have (one of the 4 was 0.5, but that's essentially zero for the purposes of intentional misalignment).  I realized afterward that this is why we were seeing IR flashes in the arm cavities according to the front wall TV - we shouldn't see those during MICH-only time, so we'll try to remember that that is a clue as to what is wrong.

These OFFSET values are also used by the new INCREASE_POWER INCREASE_FLASHES states that are helping to get the green arms locked when the optics are quite misaligned (this new state is probably related to why we haven't had to do very many initial alignments lately, which is awesome!).  Perhaps these OFFSET values weren't reverted after the testing work done yesterday with this state or they were left over from some other work or losing lock part way through the new state, so when the ALIGN_IFO guardian tried to misalign the ETMs it correctly turned on the OFFSET, but nothing really happened since the offsets were zero.

I reverted the values via SDF (SDF knew that the values were wrong, but it's hard to know which things that SDF says are differences are the things that are actually causing the problem...), and the initial alignment continued forward as normal.

Since this (incorrect offset values) is something that has caused us trouble a few times lately, TJ has been in contact with StuartA at LLO about modifying the suspension guardian to ensure that the offset values are set correctly every time we request the misaligned state.  We had decided to push this modification to January, but this is a good reminder that we should pick it up soon after the holidays, just in case this happens again.

EDIT: Corrected state name - thank you Corey!

Jim suggested this a while ago, and it looks like he and TJ prepared a guardian state for it, but I've just set the nominal for the SEI_DIFF guardian to be CORNER_CPS_DIFF.  This state has all of the vertex CPS DIFF turned on (HAM2-HAM3, HAM4-HAM5, and ITMX-BS-ITMY), but no CPS diff down the long arms. 

The microseism isn't quite high enough right now to see lots of low frequency glitches when the system is on including the arms, so I don't have a good on/off plot to show.  The microseism is increasing though, so hopefully we'll see throughout the day that the low frequency glitches don't increase.

Offline, we'll continue trying to understand how we can use the CPS diff up at higher frequencies to cover the microseism, as well as how we can have it on the arms without causing extra noise.

I have prepared an update to the H1CALCS filterbank, for the L1,L2,L3 stages for ETMX and ETMY - as LLO did last month.

The changes incorporate:

• testmass mass value update
• violin mode frequencies update
• uim dynamics update

I have included a plot of what the new filter for the uim will look like in foton. In the minimum realization step of simplifying this new feature of the model to be foton friendly, a lot of features were cut away, and we're basically left with a single feature at 152 Hz.

If there is some downtime today (like an earthquake from Paraguay), I will be implementing this update, and enabling the new uim filter in the frontend.

TITLE: 12/24 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 117Mpc
OUTGOING OPERATOR: Niko
CURRENT ENVIRONMENT:
    SEI_CONF state: WINDY
    Wind: 2mph Gusts, 1mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.26 μm/s 

Microseism is at about 0.2um/s (so will keep CPS Diff ON).  
QUICK SUMMARY:

Niko just finished the PEM Injection.  Since this was slated to be a "Maintenance Day Light", decided to go back into OBSERVING (L1 & V1 were in OBSERVING).

I waived OFF Karen's cleaning at the end stations & LVEA since it wasn't on our list of activities for today.  Speaking of which....

Will transition to PREVENTATIVE MAINTENANCE as soon as we have Accepted Activities begin.  Here are items listed on the board:

• VAC:  Turbo work at MY & EY (measurements on the floor by Kyle/Gerardo). *
• Commissioning/Fixes related to Guardian
• CAL:  If h1 breaks lock, Vlad has Calibration Filters he would like to load.

* For measurements out on the floor, I was not totally sure as to how to handle BRS.  Texted Jim and he suggested going to:  WINDY_NO_BRSY

TITLE: 12/24 Owl Shift 08:00 – 16:00 (00:00-08:00), all times posted in UTC

STATE of H1: Preventative maintenance

INCOMING OPERATOR: Corey

SHIFT SUMMARY: Quiet shift, nothing to report. Locked 14.5 hours.

LOG:

15:45 (07:45) Leaving Observing to run PEM magnetic injection

Ops Shift Transition: 12/24/2019, Owl Shift 08:00–16:00 (00:00-08:00) - UTC (PT)

State of H1: Locked

Intent Bit: Observing

Weather: 0-5 mph wind

Primary 0.03 – 0.1Hz: 0.01 um/s

Secondary 0.1 – 0.3Hz: 0.3 um/s

Outgoing Operator: Jeff

Quick Summary: Locked and Observing almost 7 hours.

Sumamry of DQ Shift for the week of 12/16- 12/22.

• Overall a great week with ( 99.93 + 67.98 + 72.99 + 91.77 + 61.28 + 99. 90 +99.14)/7 = 84.71 %  analysis ready time, little over O3b average of 79.7 .
• Range was ~ 115 Mpc  most part  of the week and crept towards ~118 Mpc during the weekend.
• Increased 10-40 Hz glitches seen on Monday and Tuesday seem to be associated with associated with high microseism and turning off the CPS diff system seems to correct som eof the issue, especially in 20-40 Hz region. (53926)
• Apparent Excess Pcal noise in PcalX due to the low frequency calibartion measurments (53951)
• Loss of observing time because of squeezer OPO crystal degradation on Wednesday. (53965) 
• Excellent weekend with interferometer locked and crusing both Saturday and Sunday.

 Since relocking at the start of the shift, all has been smooth sailing. We have been triple Observing for the past 2.5 hours. The range is 118.0Mpc. Winds are Light Air. Microseism is still elevated, but the slope is flat. 

   Lost lock at 23:45 (15:45) after a mag 4.9 EQ near Vancouver Island. The IFO was relocked at 01:19 (17:19) without operator intervention. Lost lock twice at INCREASE_POWER. The third time through, made it to NLN and back in Observing. 

H1 was in OBSERVING for about 40min this afternoon (until a smaller aftershock knocked us out yet again!).  But when we were at NLN, had a couple of SDF Diffs (see attached for channels) for: 

1. ISI ITMx TRamp (chose to NOT MONITOR)
2. SEI PROC (ISI_DIFF was in ON state.  This basically means we have the new CPS Diff in the ON state (I phoned Jim and he walked me through this new system).  He suggested we NOT MONITOR this channel, but I think in a rush to get back to OBSERVING, I ACCEPTED instead.)

Note On CPS Diff

This had been OFF, but for some reason it was ON for my most recent lock.  I called Jim and so he could help me out---this is a new system from Jenne, Chiari, & Jim.  I mentioned that with all the EQs, I had tried to transition the SEI_CONF to EARTHQUAKE & Large EARTHQUAKE a few times.  Thinking possibly this is how CPS Diff was turned ON, but that's a guess on my part.  Anyway, it was ON according to SDF & Jim explained it to me.

For better performance in the wind/earthquake bands, we run with CPS DIFF--->  ON (see alog).  Jim suggested to leave CPS Diff ON.  It is good to leave ON as long as the microseism is below 0.4um/s (we are currently at about 0.15um/s).  

If microseism gets above 0.4um/s (and it looks like we are getting glitches in DARM), then we should transition CPS Diff to OFF.  Jim suggested one can do this by going to the SEI_DIFF Guardian Node and taking it from FULL_DIFF_CPS state to the DOWN state.  Alternatively, one can also turn the CPS Diff bit to the OFF state on the Output Limiters medm.  The attached screenshot shows ISI_CONFIG, the SEI_DIFF guardian node, and the LSC Output Limiters medm  (the ways to turn CPS Diff OFF are circled in green & have arrow pointing to them.).

TITLE: 12/23 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 110Mpc
INCOMING OPERATOR: Jeff
SHIFT SUMMARY:

Today's shift was dominated by EQs!!!  Only about 52mins of OBSERVING!!! When the Earth gave us a quiet window, H1 would certainly go to NLN, but then we'd get another EQ!

LOG:

• 15:52 (& 16:07) EQ Alert for 5.7 Guatamala EQ
  • 15:55 Niko takes H1 to EARTHQUAKE
  • 16:00 L1 loses lock
  • 16:09 Predicted R-wave time elapsed
  • 16:10 (Niko leaves.)  Begin to see ASC & IMC signals increase
  • 16:11 CPS begin to increase
  • 16:13 Real R-wave effects appear to show on STS's
  • 16:18 Lockloss (after 64hr50min lock) & Observatory Mode taken to EARTHQUAKE
  • 16:20 R-wave begins to drop!  (if only we could have lasted a couple more minutes!)
• 16:26 Locking
  • Lock #1
    • 16:28 1st Increase Flashes begins
    • 16:34 2nd INCREASE FLASHES for y-arm
    • Begin to intervene!  But had lockloss at FIND IR (but also have another close EQ!)
  • Lock #2
    • Intervened with CHECK MICH FRINGES.  BS tweaked and had life for PRMI!
    • At OFFLOAD DRMI, transitioned SEI_CONF back to WINDY at 17:20 w/ blrms sei at 0.1um/s for 0.03-0.1Hz.  Then continued on to NLN.
    • 17:25 Lockloss at CARM TO TR
  • Lock #3
    • 18:18 Made it to NLN
• 16:50 EQ Alert:  5.1 off of Vancouver Island!
• 17:06-20:17, 21:54-22;36 Vlad to Optics Lab
• 17:25 Rahul Loads Coefficients for CFCs on CDS Overview related to violin modes---we are all GREEN again!
  • These violin filters rung up ETMx
  • ~19:10 h1susetmx violin mode filter changes were backed out by Rahul/Dave 
• 17:25 TJ doing BRIGHT FLASHES work on x-arm
• 18:18 NLN
• 19:12 OBSERVING...BUT....
• 19:16 EQ Alert:  5.6 off of Vancouver Island!  All Test Mass ISI chambers tripped!  Went to LARGE_EQ_NOBRSXY!
• 19:17 Lockloss!
• 19:51 All SEI & SUS recovered from Watchdog Trips
• 19:51 Nearby EQ Alert!!  (5.8 off of Vancouver Island)
• 21:21-21:29 Beckhoff check in CER (Richard)
  • 21:31-21:54 Beckhoff check at EX CER (Richard)
• 21:24 Wind fence checks (Jeff J)
• 22:21 SEI_CONF from EARTHQUAKE to WINDY
• 22:47 NLN!
• 23:05 OBSERVING!
• 23:43 Observe several glitches:  probably another nearby eq!
  • LSC, ASC, IMC signals all increase
  • 23:44 Transitioned to SEI_CONF to EARTHQUAKE
• 23:45Lockloss! 
  • This was most likely due to an EQ:  4.9 NW of Vancouver Island (No Verbal Recived)
• 23:52 Starting to relock & handing off to Jeff B
• 23:56 SEI_CONF taken back to WINDY
  • Just saw that we had a lockloss at INCREASE POWER :-/

Upon being made aware that the Corner Station instrument air compressor(s) were creating a measureable noise in the IFO (see https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=53248), we have made various attempts to reduce or eliminate this.

Recall that 50 -100 psi is required to hold the 44" pneumatic gate valves GV5, GV6, GV7 and GV8 open.  To do this, we use air compressors and dryers remotely located in the chiller yard and then route this to the LVEA via piping.  The compressors are isolated from the ground via spring mounts and are isolated from the building via a flexible connection to the piping.  Our first attempt at noise reduction was to shut-down the mechanical compressors and dryer, isolate them from the building piping and to then substitute regulated compressed bottled gas (N2) on the building side of the isolation.  This is the preffered solution as it is the quietest but the numerous small leaks-to-atmosphere currently present in the building piping rendered this a maintenance nuisance - requiring frequent bottle changes (see https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=53271). 

Next, we realized that the piping leaks which proved a significant loss when using the bottle-supplied gas were quite insignificant when compared to the constant loss-to-atmosphere associated with the continuous regeneration of the "swing style" desiccant dryer when using the compressor system.  For this system, one desiccant tower dries the a majority fraction of the air supplied from the compressors and then routes this dry air the LVEA.  Simultaneously, a minority fraction of the air supplied from the compressors gets routed through the 2nd tower during its regeneration phase.  This "regeneration" air exhausts to atmosphere.  This system works excellent as a drier but is wasteful and requires that a constant supply of compressed air be exhausted to atmosphere.  

The recent configuration changes incude the addition of check valves downstream of the dryer (prevents building air from backflowing to atmospher via regenerating drying tower when the compressor is off), moving the pressure switch sampling from the compressor receiver tank to downstream of the newly installed check valves (prevents compressors from starting if the auto drain depressurizes the compressor receiver tank), the addition of a NC solenoid valve between the compressors and the dryer (prevents compressor receiver tank from supplying regerating drying tower when the compressor is off) and the rewiring of the auto drain solenoid valve such that it only becomes energized when the compressor is running (prevents unnecessarily depressurization of the compressor receiver tank during off periods). 

TITLE: 12/20 Owl Shift: 08:00-16:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 115Mpc
INCOMING OPERATOR: Camilla
SHIFT SUMMARY: an active night for H1, in and out of Observe, currently in Observe
LOG:

• 08:53 - H1 in Observe
• 11:57 - H1 in commissioning - lockloss, alog 54006
• 13:52 - H1 in Observe
• 14:16 - H1 in commissioning - ITMX mode8 rung up
• 14:43 - H1 in Observe - range at 110Mpc, and violins damping, though beginning of this stretch stil has excess violin mode noise
• 15:04 - H1 in commissioning - beam diverter /  SQZ, H1 out of Observe
  • this corrected itself for about 3 minutes, then 9 more cycles in about 20 minutes
• 15:37 - H1 in Observe
• 15:38 - H1 in commissioning - beam diverter /  SQZ, H1 out of Observe
  • manually cycled the beam diverter, SQZ locked
• 15:53 - H1 in Observe
• 15:55 - H1 in commissioning - beam diverter /  SQZ, H1 out of Observe
  • took every SQZ guardian to Down, then Init, then relock
• 16:00 - H1 in Observe

Violin Current State:

• ITMX: modes 7 and 8 have modified damping gains
  • mode 7 nominal is +10, was at +20 for over 2 hours, set back to nominal of +10
  • mode 8 nominal is +10, currently at -4, lscparams gain new set to -4
  • violin guardian will need to be reloaded to encorporate new mode 8 gain sign
  • modes 7 and 8 should be watched at next relocking
• ETMYL modes 1 and 6 have modified damping gains
  • mode 1 nominal is 0.1, currently at 0.5
  • mode 6 nominal is 0, currently at -2
  • these are working, but not ready for prime time

In order to understand the angle to length coupling, we made some A2A and A2L to DARM transfer function measurements, few weeks ago,  using broadband excitations and noticed some phase mismatch between the measurement and the model as seen in the first attachement [AngletoDARM_20191126.png].

In order to make sure the phase mismatch, we observed, was not due to some non-linear coupling due to the high coherence excitations, we made additional measurements using sinusoidal exciations with few different amplitudes. The second and third attachment [ 2019-12-04_A2LEXC_DARM_38W.png and 2019-12-04_A2AEXC_DARM_38W.png] below show similar phase offset that we saw in our broadband injections ( ~10 deg compared to model) for both A2A  to DARM and A2L to DARM measurement.