Maintenance Timeline:

• 23-04-19 15:10 JaffB to End Stations
• 23-04-19 15:10 Karen to Mid Stations
• 23-04-19 15:10 Sheila to LVEA
• 23-04-19 15:10 Sheila out of LVEA
• 23-04-19 15:14 Robert to the LVEA
• 23-04-19 15:16 JeffB back from end stations
• 23-04-19 15:20 Robert to the PSL
• 23-04-19 15:23 (08:23) Chandra - Going to H2 to prep for vacuum system changes
• 23-04-19 15:34 (08:34) Niko, Sharon, - Going to End-X for PCal measurements
• 23-04-19 15:40 (08:40) Vanessa - Going to End-X
• 23-04-19 15:40 (08:40) Filiberto, Marc - Cabling in the ECR
• 23-04-19 15:42 (08:42) Niko - Taking End-X to Laser Hazard
• 23-04-19 15:45 (08:45) Chris - Going into the LVEA for battery testing
• 23-04-19 15:46 Richard and Sheila out of LVEA having swapped to a new REFL PD
• 23-04-19 15:47 (08:47) Christina - Going into the LVEA for inventory checks
• 23-04-19 15:58 (08:58) Cheryl - Focusing camera at HAM2
• 23-04-19 16:04 (09:04) Hugh - Going into the LVEA for inventory
• 23-04-19 16:10 (09:10) Sheila - Out of the LVEA
• 23-04-19 16:14 (09:14) Take IFO to Down
• 23-04-19 16:16 (09:16) Karen - Out of End-Y
• 23-04-19 16:16 (09:16) Chris - Out of LVEA - Going to End-X for battery checks
• 23-04-19 16:17 (09:17) UniFirst - On site to service mats
• 23-04-19 16:20 (09:20) Rahul - Runing charge measurements at End-Y
• 23-04-19 16:22 (09:22) Hugh - Out of the LVEA
• 23-04-19 16:32 (09:32) Vanessa - Finished at End-X
• 23-04-19 16:32 (09:32) Vanessa - Going to LVEA
• 23-04-19 16:34 (09:34) Narco - On site N2 delivery to CP2
• 23-04-19 16:35 (09:35) Kyle - Going into the LVEA
• 23-04-19 16:47 Kyle out of the LVEA
• 23-04-19 16:55 ChrisS leaving MY going to EY not in VEA
• 23-04-19 17:30 ChrisS moving the forklift
• 23-04-19 17:31 PSL down for water leak
• 23-04-19 17:51 Sheila to EY for GREEN troubleshooting
• 23-04-19 17:51 Fil to EY for cabling
• 23-04-19 17:52 Jason is restoring the PSL
• 23-04-19 17:59 DaveB to EY and EX CERs to label electronics
• 23-04-19 18:01 Paradise Water on site
• 23-04-19 18:19 Roberts crew into LVEA to remove cables-equip
• 23-04-19 18:38 ChrisS to LVEA to unplug the forklift
• 23-04-19 18:48 ChrisS out of the LVEA
• 23-04-19 18:53 DaveB back from one End Station, other deferred to
• 23-04-19 20:27 Craig to the LVEA for IMC measurements
• 23-04-19 20:27 Sheila and Fil to EY to look at and restart the green laser
• 23-04-19 21:07 Sheila and Fil back from EY - green laser is back on

There have been several times recently when operators had trouble relocking the squeezer after it unlocks and takes us out of observing, which seemed to be solved by re-requesting different states from the squeezer guardian. 

The reason the squeezer knocks us out of observing is because the SHG PZT hits it's rail, this seems to be happening ~once or twice a day. 

The reason the squeezer wasn't relocking is because the beam diverter wasn't re-opening after the squeezer relocked.  The problem was that the beam diverter won't respond to multiple requests to move that happen too soon after each other, and in some places the guardian was making the requests to rapidly.  

Daniel added a channel for the beam diverter called "busy" which can be checked before making a request of the beam diverter.  This problem should be avoided with changes to the SQZ_MANAGER for the time being, but in the future we can have a busy check for the beam diverter.

Attached below are the results for the OPLEV charge measurement for ETMX and ETMY. The bias voltage for ETMX is between 10-20V (except for one case for Yaw which is around 30V). The bias voltage at ETMY is between 0-10V. The bias voltage measured for both ETMX and ETMY are still not high enough, which would require a sign flipping. 

Once the measurements were complete, all the values were restored.

WP 8105

CER network secondary power supply is now connected to -48V from UPS.

F. Clara, R. McCarthy, M. Pirello

   On 04/22/19 took a set of photos of the ITM Optics. Shots were taken with the IFO locked at 35w of power. 

   ITM-X photo: Frame #5, 1/160, ISO 200, Focus 1625
   ITM-Y photo: Frame #6, 1/250, ISO 200, Focus 1625

   The shots select were a bit under exposed, which helps show the point reflections, but not so under exposed as to hide the EQ screws, which can be used as a point of reference. 

        

We had a small leak in a PSL hose, which is fixed, and there was no damage, but it did delayed some work, which is going on right now, so we're running over the noon mark for ending Maintenance.

• Currently:  Fil and Sheila at EY
• Still to do: DaveB/Daniel/Patrick DAQ Restart for new channels in EY and CS

   This morning Robert noticed water on the floor of the PSL enclosure. Inspection showed the leak to be at the barb fitting on the output side of the Diode chiller filter. There was a bulge in the hose from the hose clamp to the end of the barb. The Teflon inner liner of the hose had failed at the barb, allowing water between the Teflon and the outer rubber, which created the leak.   

   Shutdown the laser and the Diode chiller. Cut out the bad section of hose and reconnected the hose to the filter. Powered up the system and noted no further leaks.     

The Corner Station is the only building that requires a continuous instrument air supply (under normal, non-turbo pumping conditions) as the site pneumatic LN2 liquid level control valves and HVAC damper adjusters have been converted to electric.  Only the pneumatic 44" gate valves in the LVEA, GV5, GV6, GV7 and GV8 still need 24/7 pneumatic air.  As such, attention to this one supply has waned.  The pressure is monitored by the CDS system but the dryness must be measured periodically.

So, today I measure the dew point as sampled near GV5 to be -24C. 

J. Kissel

Given that
    - We've recently identified that glitching around 60 Hz in certain event trigger generation metrics has been a result of the 7.93 Hz PCAL EY calibration line, (LHO aLOG 48418), 
    - The GDS pipeline's calculation of the time-dependent correction factors for the SRC detuned optical spring (f_s and Q_s) has stopped using the 7.93 Hz calibration line, and its results are consistent with the reference model,
    - that the front-end code that duplicates this calculation has been busted since we've had a pro-spring,
there is no longer a use for this now detrimental calibration line.

Thus, today, this morning, during maintenance, I have turned off this calibration line, and it will remain so in all future observation segments.

Note, that this also reduces the RMS requested drive from 6163 DAC counts to 5043 cts.

All other lines requested from the PCAL EY remain -- 17.1 Hz, 410.3 Hz, and 1083.7 Hz.

Attached are the screenshots of the SDF capture (done in both safe and OBSERVE snaps), and an ASD of the DAC request.

Stay tuned for details from @DetChar about the reduction in glitch rates.

Both PSL power watchdogs were reset at 16:05 UTC (9:05 PDT).  This completes FAMIS 10707.

   Niko - Tanking End-X to Laser hazard

   All three (EX, EY, CS) vacuum pumps are running normally. Made a minor pressure adjustment at EX and CS. EY did not require any adjustments. 

   Closing FAMIS task #8557

TITLE: 04/23 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Preventive Maintenance
OUTGOING OPERATOR: Ed
CURRENT ENVIRONMENT:
    Wind: 6mph Gusts, 5mph 5min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.15 μm/s
QUICK SUMMARY:  Maintenance has begun, still locked at Sheila's and then Robert's request.

TITLE: 04/23 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 92Mpc
INCOMING OPERATOR: Cheryl
SHIFT SUMMARY:
LOG:

14:32 Squeezer dropped out and took H1 out of Observing.

14:35 Jeff B out to Ends for dust monitor check

14:37 Squeezer recovered and intention bit reset.

14:45 taking H1 to Commissioning mode to run PEM script

14:57 Karen out to EY

15:00 Handing off to Cheryl

ran at 14:45UTC

Made it to NLN & handful of SDF diffs.  Went through the diffs while PEM injections were going on. 

1)  H1:SUS-MC2_M1_DRIVEALIGN_L2L_SW1R was saved in a wrong state with this OFFSET "on". 

(Note:  Jenne gave guidance about this channel.  It is avail to turn "on" if we are having trouble locking the IMC & want to give it a little bump to help locking.  But we should remember to turn this "off" as soon as the IMC locks.  So this must have been Accepted when it was accidentally left "on".  Anyway, tonight this offset was in the correct "off" state, and had the diff, so we ACCEPTED.  Jenne fixed this issue for the future by adding a line in ISC_LOCK to turn OFF this offset--I believe she said in the PREP_FOR_LOCKING state.)

2) ECAT PLC1 Had Diffs (SDF diffs screenshot #1 attached) Due to ALS Remote Motorized Polarization Controller (medm screenshot #2 attached)

Not really sure why we're monitoring these channels (i.e. the Paddle X, Y, & Z channels) because these channels change whenever we make remote polarization changes.  So, I unmonitored these three channels.

3) SPM Diff for TRamp for ISI EY

For some reason the Stage 2 Rx & Ry TRamps were 0 and SPM had a set point of 5.  Since this is benign, I changed the TRamps to 5, but this then gave us new SDF diffs---which I ACCEPTED.

J. Driggers, J. Kissel, L. Sun

Today, during the calibration measurement time, we've done the following:
(1) Tuned the calibration line heights such that the uncertainty of each line is now roughly 0.2%. 
    2019-04-17_TuningCalibrationLineAmplitudes_Uncertainty.png shows the time series of the uncertainty for all calibration lines over many hours before and after the line amplitude change -- the middle section is where they were turned off for the standard suite of calibration sweeps; before they were at their former value, after they were at their current value.

(2) We realized the discrepancy between GDS production of kappa_C (the relative optical gain correction) and f_cc (the cavity pole frequency) and CAL-CS was because in the heat of battle yesterday, we neglected to update the value of the necessary one clock-cycle delay to 410.3 Hz in the PCAL DEMOD -- i.e. it errantly remained as the delay value at the former calibration line frequency at ~331 Hz. Fixing this error returned the time-dependent correction factors to the expected values from the reference model: kappa_C = 1.00 +/- 0.01, and f_cc = 410.6 +/- a few Hz (as opposed to the brief period yesterday between after the calibration line frequencies and now, where the cavity pole was reporting in the 425 Hz region, and the optical gain correction was reporting 0.97).
    2019-04-17_FixingPCALDEMODPhase_410Hz_Fixes_TDCFs.png shows a screenshot of the current values.

(3) We gather a collection of broad-band PCAL injections, as well as the standard sensing function sweeps.
Times of broad-band PCAL injections: 2019-04-17 20:13:20 UTC for ~2 minutes, and again at Apr 17 2019 20:15:31 UTC.
    /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Measurements/FullIFOSensingTFs
        2019-04-17_H1_DARM_OLGTF_SS_5to1100Hz_15min.xml
        2019-04-17_H1_PCAL2DARMTF_BB.xml
        2019-04-17_H1_PCAL2DARMTF_SS_5t1100Hz_10min.xml
The data remains remarkably consistent with the reference model (see 2019-04-17_H1_sensingFunction_mcmcModel_vs_measurement.pdf ).
We've stacked all the recent sensing function measurements without correcting for time dependence to form an estimate of the frequency dependent, time-independent systematic erro with a Gaussian process regression, and it shows the same consistency (see 20190416_ref_model_H1_sensingFunction_GPR_on_AllSensingMeasurements.pdf)

More details to come.