Yesterday, all the ISI and HEPIs were deisolated to check the fluid system Accumulators' gas charge.  All HEPI and ISI DC positions are held by the Isolation loops except for the BSC's ISIs.  I reviewed these platforms' cartesian positions and the ETMYs RX tilt has the largest shift at 3urads, ITMX RX delta is 1.5urads.  Some positions change by a couple ums: ETMY X shifted 2um, ITMX X shifted 1um.  All other shifts are a few hundred nm or nrads or less with most being less than 100nanounits.

I don't think the SEI is contributing to alignment difficulties.

I got suspicious about PMC length locking offset and changed H1:PSL-PMC_INOFFSET.

Increasing it by 1.7mV decreased the PMC length feedback by about a factor of 2, and 1st loop out of loop sensor by a factor of 4 or so, which doesn't make sense. In the attached, red and green are with nominal 3.1mV offset, blue and brown are with 4.8mV.

(After this measurement I noticed that Daniel increased the length gain from 16 to 28dB and forgot to bring it back. This measurement is with 28dB locking gain, but it still doesn't make sense.)

What's the nominal signal level for PMC demod? Is it tiny? When is the last time the PMC demod phase was optimized?

 Ops Shift Log: 10/26/2016, Owl Shift 07:00 – 15:00 (00:00 - 08:00) Time -  UTC (PT)
State of H1: IFO is unlocked. Working on relocking after the maintenance window
Intent Bit: Commissioning
Wind: Is ranging from Calm to Light Breeze (0-7mph)
0.03 – 0.1Hz: Currently at 0.07um/s – Ringing down from EQ
0.1 – 0.3Hz: Trending lower – Currently at 0.8um/s
Outgoing Operator: TJ
Incoming Operator: Travis
 
Activity Log: Time - UTC (PT)
07:00 (00:00) Take over from TJ
07:45 (00:45) Adjust Dust Monitor alarm levels
12:18 (05:18) Put IFO into DOWN, due to alignment and locking troubles 
13:30 (06:30) End Shift early. 

Shift Details:
Support: Sheila 
Shift Summary: IFO unlocked. 

After a difficult but successful Initial Alignment by the Evening shift, working on relocking. After a long night (very long for Sheila) of many tweaks were able to get the IFO to lock at DC_READOUT once for about 30 minutes. After this lock broke we were unable to get past green locking. There are problems with INPUT_ALIGN hanging at LOCKING_XARM_IR, (see aLOG #30881). Sheila did not think there was much chance of successful locking. I put the IFO into DOWN to await the refreshed minds and fingers of the day shift to continue the good works of the past two shifts.

 Sheila & Jeff B.
 
 Over the past few shifts the ALS green power build up in the X arm has steadfastly remained below 0.95 despite all tuning efforts. The Y arm build up as been normal. We trended the X Arm DC power. On the 24th the power of the green laser dropped from 1.02 to 0.95, (trend posted below).       

   

After making a minor modification to a pair of mirror mount supports, a pair of Picomotor equipped mounts
were installed on the PSL table.  These mounts steer the beam into the pre-modecleaner, the controls for
which are accessible from the ISC Picomotor MEDM screen.  Picomotor A (aka #1) is the one furthest from the
pre-modecleaner and closest to the high power oscillator, B (aka #2) the one closest to the pre-modecleaner.
Yaw controls are X, pitch Y.

    The modification made to the base was to avoid crushing the flat cables that come from the Picomotors.

    Work performed under work permit #6268.


Rick/Jason/Peter

This afternoon Kiwamu and I plugged the DBB back in.  When we did this, the PSL external shutter closed; Peter King said that it is a know issue that shutters close randomly when you power things on or off in those racks. 

I also took put a 1/100 divider on the BNC connector from the 18V rack power, AC coupled it with a 560 and plugged it into LSC_EXTRA_AI_1.  The plan is once we are locking to try another test of the DBB shutters, and see if it still has an impact on our nosie with the TCS and alingment changes from last weekend.

We have had trouble with alingment since maintence day today.  There were several things that happened that could potentially impact alingment: SUS models were restarted, HEPI work, and adding picomotors to the PSL before the PMC.  The PSL work is probably the most likely culprit.  I hope that we will be more selective about what we choose to do on maintence day from now on.

Alingment symptoms:

The PMC alingment is not as good as it had been.  There were also shifts in the alingments of MC1+3, especially in yaw.  Were these from model reboots or did someone intentiaonally change them to relock the mode cleaner?  The spot on IM4 trans move from 0.2 in yaw to -0.35 or so.  TJ and I trended all the IM osems and they hadn't moved much, but we restored the small changes.  Once Jeff B and I finally got the IFO locked (I engaged the soft loops one at a time by hand), our recycling gain was very low (below 24).  I tried to move MC1+3 in yaw to restore the position on IM4, both earlier with TJ and with the full IFO locked, the MC WFS generally drag it back to where it was.  With the full IFO locked I moved IM3 in yaw, which did help the recycling gain (I chose IM3 because it's after teh Faraday, not because I think it is what moved).  I moved it too fast and broke the interferometer lock, so we finished using it to restore the position on IM4 Trans with just the mode cleaner locked.  We partially reverted this because we saw no flashes in the arm, and are going to give up for the night now.

If we still have this problem in the morning, it is probably worth taking a look at the irises that Cheryl placed on the PSL table a while ago to see if the beam goes into the IMC with the same alignment.

REFL WFS don't work for PR2 at 2 Watts:

I changed the ISC_LOCK guardian back to using POPX WFS for acquisition.  The point of the POPX WFS is that they can be used even when inital alingment isn't great and the recycling gain is low, so we would like to keep them on for power up and switch to REFL WFS in LOWNOISE_ASC.  I've put some code in low noise ASC to switch back, but we haven't gotten to test this yet. I guess that the matrix to use REFL to control PR2 was probably tested at 25 Watts last night but set up in the guardian for use at 2 Watts, because Jeff B couldn't engage the REFL WFS yesterday morning after commisioners left.  Tonight it was clearly breaking the lock, which might have been partly because of our bad alingment, but when we changed it back to POPX it was fine. 

Initial Alignment changes:

Jeff B and I just made a few changes to initial alingment, after TJ, Evan, and I had difficulty with input align earlier in the night.  Although our alingment change today probably contributed to this, I think the changes are good and things I've been meaning to do for a while anyway.

• We re wrote the REFL WFS Centering states to be identical to the WFS centering states used in DRMI, without the AS loops.  This was beacsue the old refl wfs centering state would not always stop the operator from continuing to align if the DC servos were railed.
• We changed the INPUT align state from using REFL WFS, which have very little light on them but were the only WFS available when we first wrote this state, to using AS45I.  These are better signals and I've been meaning to make the change for a while now.  To do this we made AS WFS centering states which are a copy of the REFL WFS centering states. 

   Reset the dust monitor alarm levels back to correct values after maintenance window. 

For some reason the ETMX bio settings are frequently being set to something inoperable. I think this is the third time I've seen these settings in the last week or two. (It happened on sunday after the CDS problems, and I think maybe last tuesday). The ESD should be set to high volts, enabled.

TITLE: 10/26 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Aligning
INCOMING OPERATOR: Jeff
SHIFT SUMMARY: Slow recovery from a big maintenance day. There were ISS struggles in the beginning, then ALS was pointed to nowhere, followed by many hours trying to figure out why the IMC was not locking. While Sheila and I had seemed to have tried everything, the MC just suddenly locked by itself. The FSS PZT Mon may have been oscillating for a while which could have caused much of the issue, but we are not 100% sure that this was the only problem for that time. Initial alignment also had PRM and SRM waaaaaay off, which meant adjusting other optics after adjusting those as well. Just finished an initial alignment and starting up the chain before I hand it off to Jeff.
LOG:

• 23:18 - Robert to LVEA for setup
• 00:21 - Rick and company back from EY
• 01:33 - Jason and Peter out of PSL

DarkhanT, Yuki Inoue (KAGRA), RickS (SudarshanK assisting with image analysis over the phone - until the phone died).

Today, we went to Yend to investigate the apparent clipping that EvanG had discovered (see entry 30827).

We found that both beams were off centered on the aperture of the Rx module integrating sphere, with the Outer (lower) beam clipping on the aperture (see attached image).  Blocking one beam and then the other revealed that the increased noise in the Rx power sensor spectrum was all due to the clipping of the Outer beam.

Camera images revealed that the beams had moved on the ETM as well (exonerating movement of the ETM as the cause of the movement on the Rx side).

Analyzing Pcal camera images we found the beam position offsets from the optimal locations were (x, y): Upper (-1.5, 1.8); Lower (-6.9, -2.5) (millimeters) Usual x,y convention: positive x, right; positive y, up.

Not knowing what had moved, we used the output steering mirrors in the Tx module to center the beams on the Rx intetrating sphere aperture (see attached photo).

After moving the beams, analysis of camera images (see attached)  gave the following beam locations (x, y): Upper (-1.4, -0.9); Lower (-1.3, -1.4) (millimeters). 

These are within our 2 mm tolerance.

We installed apertures at the output of the Tx module and at the input (just upstream of the steering mirrors) in the Rx module.

We will repeat the Yend calibration using the Working Standard as soon as possible.

Keith found the source of our full disk. When md5 checksums where added to the frame directory the NDS server began logging error messages for each non .gwf file that was found.  This ended up contributing to huge log files +90GB.

We have updated the nds process to quiet these messages as this is no longer an error condition.

See work permit 6280 and bug 1054.

Cyropump #4 was generating alarms today, both before and after Dewar fill. After trending signals, it appears the LLCV and exhaust noise has been growing over time. Pump fill level and LLCV setting stabilized after I opened the bypass exhaust valve. Wondering if the check valve is faulty. Will test tomorrow. I have removed and reinstalled it a couple times in the last month with TC testing.

Kyle, Chandra

We ran all QDP80 roughing pumps on site today for maintenance and for refresher (WP 6269); checked for gross leaks in foreline/turbo volumes. Found one at MX.

EY
as found pressure
foreline = 14 Torr
turbo = 0.58 Torr
after rough pump down and following valve isolation
foreline = 0.040 Torr
turbo = 0.036 Torr

MY
as found pressure
foreline = 2.3 Torr
turbo = 0.60 Torr
after rough pump down and following valve isolation
foreline = 0.013 Torr
turbo = 0.022 Torr

LVEA - vertex
as found pressure
foreline = 2.2 Torr
turbo = 0.67 Torr
after rough pump down and following valve isolation
foreline = 0.017 Torr
turbo = 0.022 Torr

LVEA - Xbeam manifold
as found pressure
foreline = 12 Torr
turbo = 0.63 Torr
after rough pump down and following valve isolation
foreline = 0.021 Torr
turbo = 0.039 Torr

LVEA - diagonal
as found pressure
foreline = 5.4 Torr
turbo = 0.54 Torr
after rough pump down and following valve isolation
foreline = 0.026 Torr
turbo = 0.039 Torr

LVEA - Ybeam manifold
as found pressure
foreline = 5.4 Torr
turbo = 0.48 Torr
after rough pump down and following valve isolation
foreline = 0.025 Torr
turbo = 0.034 Torr

MX
as found pressure
foreline = 780 Torr
turbo = 1.0 Torr
after rough pump down and following valve isolation
foreline = leaking
turbo = 0.084 Torr

EX
as found pressure
foreline = 6.6 Torr
turbo = 0.43 Torr
after rough pump down and following valve isolation
foreline = 0.017 Torr
turbo = 0.026 Torr


The leak in the X-mid fore line is between the Turbo Header isolation 
valve and the Turbo fore line Safety Valve. Removed and examined the 
NW seals but nothing obvious.

We verified each QDP80 shuts down with the absence of N2 purge seal gas supply except the Y-end QDP80 which did not shut down.

Y-mid pump turned off due to overheating because cooling water was not valved in initially. It leaked a small puddle of coolant and ran OK upon cooling.

We pumped down the purge air line in LVEA unintentionally.

FRS 4559
WP 6247

EX:

1. Placed HWS camera on seperate power supply. The power supply is underneath the ISCTEX table.
2. Finished cabling for RGA at EX.

LVEA:

1. Placed HWS cameras (X & Y) on seperate power supplies.
2. Terminated network cable for RGA in LVEA. Network cable is pulled to SUS-R3. Connection to switch needs to be made in CER.
2. Placed power distribution boxes (24V regulated down to 12V)  for the ITM spool cameras, for both X and Y arms.
2. Placed junction box and landed power cables on top of H1:SUS-R5. This is part of the ongoing work for the 24V digital power distribution.
3. Started work on junction box on top of H1:SUS-R6.

The software for the HWS cameras needs to be restarted.

F. Clara, E. Merilh

WP 6276

[Changed the power level on PDA]

I went into the PSL today and changed the ND filter that was screwed on the PDA photodetector module (30415) in order to change the power level of the photo diode. Before the change the PDA DC singal read a relatively small value of 2.2 V. After the change, the DC signal became 3.8 V which is close to what PDB says 3.9 V. Indeed, the voltage readouts for the two diodes shown in the medm became close to each other (~ 4.5V). The new ND filter is actually a stuck of 0.2 and 0.5 abrorptice ND filters. It was an ND1 before.

[New setting for ISS inner loop]

The gain slider now should be 18 dB (which used to be 30 dB, 30415). This gain gives us a UGF of 54 kHz. This means that the open loop transfer function is almost identical to the one with PDB used as the in-loop sensor (29942) as expected. In fact, we can now switch the sensor between PDA and PDB without changing the reference offset or gain while keeping the loop closed. Though this typically changes the diffraction power by a few %. The new gain is now accepted in SDF.

The attached is a plot of the measured open loop transfer function with PDA. Also the raw data is attached. Also, I attach a noise spectrum seen at one of the analog output for measuring the transfer function.

M. Pirello, A. Ramiez,  E Castrellon

Work Permit 6271

Per ECR E1600292 we applied the VCO capacitor mod to all 5 VCO's in the corner station and one at each end station.  This process includes replacing the 10nF capacitors on C79 and C80 with 2uF capacitors, and checking the voltage rails to verify elimination of the 420kHz oscillations.

Corner Station Units:

S1200563, S1200559, S1200560, S1200564, S1200558

End X:

S1200561

End Y:

S1200566

Notes:

End X, there was a very inconvient clean room pole directly in the path of extraction for the VCO from the rack.  We had to relocate 2 chassis to angle the VCO enough for removal.  All chassis were put back in their original positions before leaving.

End Y, this VCO required more capacitance to remove all of the 420kHz noise on the -24V Rail, with the addition of a 2nd 2uF capacitor, the noise was eliminated.

We recorded AI output of PCAL injection as well as PCAL_DAC_FILT thing together with witness GPS 1pps using Tektronics MSO4043 (1 sec with 1Msample per channel, and 2 sec with 1Msample per channel).

We also recorded the digital output of the PCAL injection as well as digital input of the PCAL_DAC_FILT thing.

Evan will look at the timing comparator data.

These will be analyzed in the near future for further timing sanity check.

Since the noise of the detector has improved around the 331.9 Hz Pcal injection frequency, we can reduce the amplitude of the injection (current setting 9000 cts for both sine and cosine). I have reverted changes that increased the amplitude of this line (see LHO aLOG 30476). The new amplitude setting is 2900 (for both sine and cosine amplitudes), which is the same as it was before increasing the injection amplitude.

This also brings the total injections to Pcal Y below the threshold (see LHO aLOG 30802). The threshold is 44,000 counts. The current total injection is now 38650.0 counts.

Screenshot of excitation settings attached.