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Entry for work done on 9/12/2017.

Before disconnecting field cabling to ISCT6 (alog 38615) both the PZT and Fast Shutter high voltage power supplies were turn off.

H1nds1 was restarted today after a crash.

The clean rooms over the following HAMS have all had soft roof covers installed and had first cleaning done.

HAM 1&2
HAM  3
HAM  4
We will continue vent prep today by getting some 2nd cleanings completed and craning items into the biergarten.

All LVEA zones are now under the control of the new HVAC controls (COMPASS FMCS)system. Only the zones and not the air handlers yet, are controlled by the new system. The 6 new sensors that were added are currently incorporated into the averaging of the zone controls, this may change.

The takeover of the air handlers is scheduled for early October, depending on vent schedule.

Others tomorrow.

In preparation for next week's vent, tested some LVEA vacuum equipment. Turned on LVEA purge air (Kobelco) unit and measured -39C dew point. Spun up three turbos (vertex, YBM, XBM) and QDP80s. Need long controls cable for vertex station. 

All systems OFF now, but left turbo power on until they spin down fully. Left water valved into Kobelco and QDP80s for cool down. 

TITLE: 09/12 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: Jim
SHIFT SUMMARY:
LOG:

16:00 Fil, Corey, Elizabeth to IOTs, moving back from chamber
16:30 Jason, Ed to PSL
17:00 Safety reviewers to LVEA
18:00 Keita to ISCT6
18:30 Chandra to EY
19:30 TVo to EX/EY
20:00 Bartlett to PSL

(Apollo [Mark, Tyler], Corey, Daniel, Fil, Keita, Patrick)

This morning IOT2R (small table), IOT2L, & ISCT6 were prepped for being moved.  Prep work included:

• Disconnecting all electrical cables from tables (Photo #1 shows Patch Panels with cables removed.  Thank you, Fil!)
• Marking the position & elevation for IOT2L & ISCT6 (IOT2R is moving from HAM2 to HAM6 & will become SQZT6 (see D1500297))
• Disconnecting bellows from chamber, covering viewports, & covering open holes on tables (See Photo #2--Patrick did most of this for all three tables, Thanks!)
• Removing any loose items on the tables or on top of their enclosures.
• Many thanks to Mark & Tyler for handling bulk of the craning work (Photo#3 shows craning of IOT2R into Squeezer Bay)

Notes For IOT2L:

• Three corners marked with plumb bob +/- 1mm & marked as "Sept 12, 2017"
• Measured elevation of 3 15/16" - 4 " (floor up to --> bottom surface of horizontal boxbeams)
• This was rolled from HAM2, to a space adjacent to the IMC Tube closer to HAM3.  It was fairly easy for two people to roll it as long as the wheels are lined up.

Notes For IOT2R: (smaller table)

• Did not mark position since it is moving to south side of HAM6
• This was rolled from HAM2 to near the Squeezer Bay and then craned into the Squeezer Bay.

Notes For ISCT6:

• Three corners marked with plumb bob +/- 1mm & marked as "Sept 12, 2017"
• Measured elevation of 3.5" (floor up to --> bottom surface of horizontal boxbeams)
• This was craned into the Squeezer Bay.

I measured the beam spot on MC3 yesterday, September 11, 2017, and found that it's +2.11mm in pitch, and -5.82mm in yaw.

Measurements from July 17, 2017, show similar results:  +2.26mm in pitch, and -5.84mm in yaw.

Above measurements are after the Montana 5.8M earthquake, and the measurement below is before.

Measurements from March 17, 2017, show: +2.16mm in pitch, and -5.70mm in yaw.

OSA controller and red MHV to BNC cable -> ISC locker outside of the sqz bay.

OSA itself is on the table.

Thorlabs PD power supply, oscilloscope -> commissioning wire rack

ISCT6 LED power supply -> SQZ bay table

Installed 5 new dust monitors in the LVEA to support chamber openings. The LVEA dust monitors are located and named:

9am local 

Turned on RGA filament at corner station. Will scan later. Beam tube GVs may be closed.

The PSL and ALS shutters have been closed and locked out.

TCSX and TCSY lasers have been disabled.

More follow-up studies, interferometer worked well, reports later. More to do but I think Ill let the last hours of the O2 IFO pass quietly. 

I did a couple more measurements of the ESD actuation tonight.

1)I re-ran the script that allows us to measure 4 coefficicents for each test mass, (described in 38387).  Plots coming soon...

2) I measured Veff by driving the signal electrodes in length while we were locked and adjusting the bias voltage to minimize the coupling to DARM.  This can be checked against the results from the first measurement.  Veff = (beta-beta2)/2(gamma-alpha)

3) For some optics I also measured a different effective bias, by driving the bias path at 12 Hz and changing the offset in the bias path to minimize the coupling to DARM.  Veff 2= (beta+beta2)/2(alpha+gamma)

Here I have written these as positive if the voltage requested out of the DAC is positive, although in reality there is a sign flip in some of the drivers (I will edit this entry in the morning with the correct sign).

J. Kissel

Charge measurements have been completed for today. ETMX remains at a low effective bias voltage, though the expected slow-and-steady charge accumulation has begun. ETMY, after last week's single-cycle TMDS discharge use (see LHO aLOG 38524), show consistent *reduced* effective bias voltage, but not nearly as well mitigated as on ETMX with a three cycle discharge. 

It's still most interesting that while ETMX's discharge has drastically reduced the (non-limiting) unexpected ISI ST2 to DARM coupling (see LHO aLOG 38507), ETMY's discharge appears to have reduced *the* mystery noise (LHO aLOG 38540), via unidentified coupling.

Just for ease of "one number reporting" I again take the mean of all pitch and yaw data points, and compute their standard deviation to form a ball-park uncertainty:
         2017-08-31     2017-09-08     2017-09-11    
ETMY      51+/-34        -21+/-12       -22+/-12 
ETMX      -4+/-3          -4+/-3         -4+/-2

Since we're replacing both ETMs in due time, I think we just don't care what the charge is beyond tomorrow, for the forseeable future.
   (a) We know that we can use the TMDS system to discharge an optic at vacuum in ~2 days
   (b) We know we can use the Bias voltage over a long time period to control / minimize the effective bias voltage
   (c) We now will be using conductive gloves in chamber, as well as plenty of dry-N2 gunning.
So may we just take this off our list of things to care about once Post O2 commissioning ceases until a pre-O3 detector begins to appear.

Thanks to T. Vo, T. Shaffer, and J. Warner for running measurements while I was out, see LHO aLOGs 38593 and 38576 for ETMX and ETMY respectively.

Patrick, Daniel, Hang, Sheila, TVo

We are back at NLN with a range of about 55 MPC.

Good news, it seems like the ETMY TMDS slightly lowered the noise floor in the 15-55 Hz band!

Attached is a spectra comparing a few different times, the first 3 are just to get a rough reference about what the noise floor was before the discharge measurement but after the Montana EQ.

It seems like ETMX discharge also helped a bit but it wasn't obvious unless you take on the order of hundreds of averages, this still doesn't reconcile all of the mystery noise but there is some progress.

J. Kissel, D. Barker

Posting some data to support a future ECR to add more violin mode banks to the QUADs, here's the CPU Cycle Turn Around Time during O2 for the front-end models that run the QUADs. The ITMs have been running around 42-45 [usec], and the ETMs have been running around 32-33 [usec] during O2 (see first attachment).

Remember, two things have happened that have *reduced* the CPU turn-around time over the past few years (see second attachment):
- the end-station front-end computers were upgrade to better CPUs back in Feb 2016 (see LHO aLOG 25474); prior to that they'd typically run at around ~55 [usec].
- All QUAD model's data storage list was pruned in Oct 2016 (see LHO aLOG 30821). This knocked about 10-15 usec off of the ITM time, and a further ~2-3 [sec] off of the ITMs.

In short: there should be plenty of CPU time to add oodles of violin mode damping filters.