3pm local

Manually overfilled CP3 today (one day early) to test redundant thermocouples at exhaust (TE202A & TE202B) after rewiring at terminal. Fill took 50 sec. with 1/2 turn open on bypass LLCV. Left bypass exhaust valve open.

TCs were both wired backward.

Also rewired CP4 exhaust TCs but still need to test (heat gun first, then manual LN2 overfill). 

The plan is to use TC read back coupled with exhaust pressure to automate CP3 fills.

NOTE:  while I was at CP4 I happened to catch an event where the exhaust pressure rose and the pump level fluctuated a lot with a drop in LLCV value. This seems to be an anomaly and could have been a delayed reaction from the Norco rep opening Dewar valves this morning during annual inspection.

The "MEDM (screen shots)" link on the lhocds.ligo-wa.caltech.edu web page has been updated to include suspension screens.

intentional move:

• delta IM2 yaw = -15urad
• delta IM3 yaw = +47urad

unintentional move due to poor IM drive diagonalization:

• delta IM3 pitch = -6urad
• delta IM2 pitch = -1urad

change on ISS2 qpd:

• delta pitch (-y) = -0.5, was -0.2, now -0.7
• delta yaw (-p) = +0.197, was -0.02, now 0.003

this change may have effected the ISS2 pd centering as well, so recentering may be beneficial

Betsy, Jason, Nutsinee, Alastair (on phone)

Procedure (written based on Alastair's experience at Livingston. somewhat useful): T1600050

Today we successfully flushed both TCS chillers. First we switched off the keys at the controller boxes. Then we switched off all the power supplies on the mezzanine (two TCS powers supplies, an RF oscillator, the AOM power supply was already off since the AOMs were taken out of the water system and not being used). Dave was going to turn off the OAF AI chasis anyway so we did a little test to see if turning off the AI chasis would trip the chiller right away. The result was the chillers were slowly driven to low temperature, they did not trip instantaneously.

Then we continued -- once Dave confirmed that the AI chasis has been turned off and the result was clear, we turned off the chillers and unplug the power and I/O cables, removed the chillers from the water systems (using the quick connects), then pulled chillers away from the wall (which has a power outlet, we also covered it with tape just in case). We had issue trying to drain the chillers as we followed the instruction. Opening and closing the drain plug did not let water through, we had to unscrewed and losen the drain "pipe" itself. we unscrewed the drain plug and plugged in hoses to allow water into a bucket. All these were not written in the instruction.

Then we noticed a lot green "stuff" sitting in the water container inside the chiller. Y chiller was worse than X chiller. We took some samples and tried our best to wipe the container clean. That red spot didn't come off by the way.

Then we reconnected the outlet pipes but left the inlet pipes disconnected. The inlet pipes had their quick connects taken out at one end pointing to the bucket. We refilled the chillers with clean lab water, plugged the power cable back in and started flushing. We didn't plug the IO cable at this point since the AI chasis were still down and I don't see a need of communicating with the front end. Plus it's just going to get in the way.

Each chiller was flushed with 10 gallons of water. The flushed water looked clean (no green tint, floating particulates). We put the quick connects back to the end of inlet hoses and reconnect them to the chillers. Once we put in new filters (which we rinsed with lab water), the filters started turning green right away. Once we made sure nothing leaked we recovered the TCS.

The drain pipe now has an extra fitting that allows a drain pipe to fit over for easy draining if we ever have to do this again.

Walked in to an H1 which was locked at NLN (Nominal Low Noise).  After that, spent a good chunk of the day focussed on Maintenance.  For the most part, it was completed 2:30.  Once we got the PSL back (it tripped), High Power measurements were first on the Commissioning Agenda.

Day's Activities:

• 7:30:  Yarm outside work all day (Chris S)
• Went over nuc FOMs with Jim.
• RO Alarms:  Contact Bubba/Richard.
• 8:00-9:25Cleaners to Ends (Karen mentioned EY was esp buggy & we received Dust Alarms there)
• SEI---to NO BRSX/Y at start of Maintenance
• 8:28:  Pull ISS Chasis & other activities (Fil & Ed)
• 8:05-8:30:  Injection (Robert)
• 8:15:  MODE 25 of PI rung up.  Took 100 to -100 & it brought it down.
• 8:20:  Working on HAM1 Cleanroom Curtains (Jeff, TJ)------>Jason who 
• 8:20-09:20:  Working on Vac computers so they can have epics (Patrick)
• 8:25-10:25:  Fire Dept to all buildings for Fire Ext inspection (Joe D)
• 8:28 - 9:30:  ITM esd Drivers (ed)
• 8:48-12:20:  NORCO LN tank annual inspection & talk with Kyle (Gerardo/Kyle notified)
• 8:58:  PSL work:  Inspect plumbing & replace cable walkthrough, periscope investigation (WP6183, Jason/JeffB/Robert)
• 9:15-1:30:  TCS Chiller Flush starting (Betsy)
• 9:22:  Site HEPI Maintenance (Hugh)
• 9:35-1105:  PCal EY Calibration (Travis)
• 9:47:  PSL Tube Shutter closed for dark measurements (Daniel)
• 10:05:  PSL Chiller tripped laser while working on plumbing (Cheryl helping at Chiller & PSL crew investigating plumbing)
• 10:13  CP4 work (Chandra)
• 10:22: Swap IO cards & watch TCS (Nutsinee)
• 10:26:  Measuring cable on floor (Gerardo).
• 11:16:  Paradise Water
• 11:00:  AS-C QPD check (Fil)
• 11:40:  IM work (Cheryl)
• 11:45: OAF AI work (Dave)
• ~12:30:  SEI Config returned to Nominal WINDY
• ~??:  Guardian upgrades (Jamie)
• 1:38 MY VAC work (Chandra)
• TJ noticed DIAG_MAIN saying the ETMy ESD was "OFF".  We toggled the HV on/off & this change the state of the ETMy ESD (Quadrants went from single digits to all negative several hundred values.)  We wondered whether it was OK to have the Bias (top value) have same value as all quadrant values.  Had Betsy take a look and she said it looked fine.
• 2:30 PSL Tripped (Jason, Terra)
• 2:30 Upgrade H1hwsex computer (Carlos)
• 3:10 50W measurement (Daniel)-----> Ongoing

Fielded a couple of Remote Access requests.   

Both servers h1hwsex and h1hwsey are now running Ubuntu 14.4. 

Work Permit 6193

The 12V power supply for the timing slaves was moved to separate power supplies, see list below. Front end computers and IO chassis were powered cycled.

IO Chassis LSC (CER)
IO Chassis ISC (EX)
IO Chassis ISC (EY)

F. Clara, D. Baker, J. Batch

Laser tripped at 21:28:53 UTC (14:28:53 PDT), according to the status screen it was the power meter flow that tripped the system.  This was likely a leftover from the work we did earlier today.  The system came up without issue and is now fully up and running.

noise in IM4 Trans yaw = 0.007

2.5urad change in IM3 yaw as seen on IM4 Trans yaw = 0.007

2.5urad change in IM3 yaw as seen on ISS2 yaw (-p) = 0.030, which is 4.3 times larger than the change on IM4 Trans yaw, and 6 times larger than the noise on ISS2 yaw (-p).

IM4 Trans yaw is a marginal signal for tracking changes in IM3 yaw alignment.

attached: noise chart, IM changes on im4t and iss2, plots of im4t and iss2

I have generated a new FIR filter bank for Hanford and tested it by running gstlal_compute_strain in partial calibration mode over 1024 seconds of data during a recent lock stretch, starting at 2016-09-27 at noon UTC (GPS second 1158926417). Kappas and strain spectra look reasonably sane compared to CAL-DELTAL_EXTERNAL_DQ. N.B., the EPICs values recorded in this new filters file are not correct, so kappas ought to be computed based on what is in the raw frames. There also appears to be an error with relative timing of the residual and control chains which is not yet resolved at either site; see the CALCS vs. GDS residual plot below and notice the large downward spike near 38 Hz. Aaron also noted this problem at LLO; see https://alog.ligo-la.caltech.edu/aLOG/index.php?callRep=28277.

The new filters file can be found in the calibration SVN:
aligocalibration/trunk/Runs/PreER10/GDSFilters/H1GDS_ 1158989379.npz

These filters were made using revision #3358 of the calibration SVN. 

Several plots are attached below:
(1) The h(t) spectrum as calibrated in partial mode using the new filter bank, and as read out of the front-end CALCS model and de-whitened;
(2) The ASD residual of CALCS vs. GDS (data calibrated using the new filter bank are of frame type TEST); and
(3) Plots of the new control and residual correction filters.

For plots (1) and (2), I had to highpass filter above a corner frequency of 8 Hz and use a 32-second FFT (with 16 second overlap) to get rid of some nasty spectral leakage. I filtered both channels identically (except for an extra de-whitening filter applied to CAL-DELTAL_EXTERNAL_DQ) and used a Kaiser window to overcome dynamic range issues. Plots of the new filters were made using the matlab code in the calibration SVN.

J. Oberling, J. Bartlett, R. Schofield

We went in to the PSL today and swapped the old cable crossover that was overflowing with a larger one, see attached picture.  The installation is not complete, the 2nd section was too long so we need to cut it.  If anyone goes into the PSL, if you need to walk across the crossover, please do not walk over the exposed cables.

While in there, we took a look at the known slow leak in the PSL cooling manifold.  Unfortunately there's nothing we can do about it in-situ; a fix will mean pulling the manifold out, which has caused us problems in the past.  Since the leak is very slow and we are working on a new manifold design, we will leave it as is for the time being.

Since we have also been seeing air bubbles in the system (seen in the fill port of the crystal chiller, most recently reported by Sheila here) we bled the system at the filter canister under the PSL table.  This initially tripped the laser (bled too much, chiller got low and shut off), so we then recruited Cheryl to fill the chiller in the chiller room as Jeff bled the system in the enclosure.  A good bit of air was let out of the system; Robert will do some analysis to see if this has improved things.

When bringing the laser back up, the PMC was having a hard time locking.  This turned out to be due to a small shift in the beam alignment into the PMC.  Best guess at this point as to why the alignment shifted is that we were in the PSL long enough for the AC to lower the ambient temperature enough to cause this shift.  I did a small tweak to the beam alignment into the PMC and everything locked up again without issue.

Calibration measurements for End Y Pcal are consistent with previous measurements.  Optical efficiency for both beams is 99.2%.  See attachment for the full report.

In alog 29940 I measured the change in alignment slider counts vs optic alignment change (on OSEMs) for all IO IMs.

I calculated and proposed new gains for the IM alignment sliders, however, today I noticed that the ratio of the current gains yaw/pitch is alomost exactly equal to my proposed gain ratio of pitch/yaw.

This is evidence that the current gains are reversed from what was intended.

Below I show that swapping the current pitch and yaw gains gives a more consistant value for urad / slider count of about 0.045, instead of the current situation where the urad / slider count in yaw is 3x pitch.  I also correct the gains to make the urad / slider count consistant and 0.050.

current alignment slider gains and urad / slider count

current alignment slider gains - swapped

alignment slider gains corrected to give 0.050 urad / slider count

Meant to make a note of this earlier, but the Maintenance deluge took over.  

H1 was locked this morning.  Apparently it had been down, but went back to Nominal Low Noise (NLN) on its own!  

While in NLN, received a Verbal Alarm at 8:14am (15:14utc) about the PI of Mode #25 was ringing up.  I took the gain from +100 to -100, and this seemed to turn it around, BUT we did drop out of lock 5min later.  Mentioned the alarm and addressing of the PI to Terra.

 
Installed and tested the scroll backing pump for the Vertex Turbo (part of a site-wide modification to main turbo pumps which allows selecting either QDP80 or scroll pump to back Turbo).  Confirmed that the Turbo's fore-line isolation valve (aka "Safety" valve) closed at the loss of scroll pump control cable connection or AC at its motor winding, i.e. that the backing pump interlock functionality remained as originally designed.  

Also - Ran both Corner Station QDP80 pumps for ~2 hours and energized all four Turbo Pump controllers (done weekly to charge levitation batteries)  

Leaving Vertex Turbo controller energized until after lunch to allow rotor to slow down after braking.

Sheila, Keita

The 3rd whitening filter does not switch for AS_C segment 3.  The readbacks look OK. 

(M. Pirello)

Per Richard's Work Permit #6092 I reprogrammed both CPS fanouts in the LVEA, and the ones on the X and Y end stations.  Programming was successful and the heartbeat LED's are now off.