Fully automated so only watchdog trips and an undamped SUS would spoil things.  When the TF is done, the Guardian will be unpaused to bring things back to nominal.

Here's some plots showing the kind of performance we have in the corner station. Nothing new here, just wanted to do a quick status update.

For the 3 chambers, we can make some general comments:

- we're reinjecteing some noise below 100mHz in X and Y

- we're hitting the noise floor pretty quickly in the rotational degrees of freedom.

- some isolation is provided by stage2, but it's not very aggressive (lot of room between 1 and 10Hz). The good thing with this configuration is that we're not introducing some extra noise at low frequency (this comment is true for ITMX and ITMY. BS is on damping only for ST2).

Jason, Rana

Rana had the idea that the ITMy problem was due to the thermal electric cooler not effectively cooling the laser therefore causing the instability we are seeing as a sawtooth yaw signal.  To test this we first increased the laser power and then decreased the laser power, both times looking to see if the sawtooth changed at all.  In the attached SUM graph:

• The first jump is when we turned the laser on after closing up the receiver box
• The second jump is Rana turning the laser power up
• The third and fourth jumps are removing the Lexan viewport cover and re-aligning the oplev
• The drop at the end is me lowering the laser power

Throughout this it can be seen that the sawtooth pattern doesn't change, so that rules that idea out.  Will continue to continue to investigate...

We've reduced the motion on PR3, especially the 'bump' seen in the optical lever pitch around 0.7Hz.

Turns out there is a good coherence between GS13 X and the optical lever in pitch. The GS13 is far away from the noise floor around this frequency, so by lowering the blend frequency in X, we were able to gain a factor of a few without introducing too much gain peaking at lower frequencies.

Also, by switching the GS13s to high gain, we improved a little our performance at low frequency in RZ/Yaw.

This configuration seems good enough for now, but the next step is to design a more fitted blend set for HAM2. I'll add that to my to-do list for next week.

Attached are the TF taken Thursday morning.  Like those seen on HAMs 4 & 5 ISI, having the HEPI unlocked and position loops closed versus HEPI on stops, the HEPI structural bumps between 10 to 40hz, are reduced in frequency and lowered in Q, see the plots in 13763 for this comparison.  Unlike HAMs 4 & 5 however, which have generic 5hz HEPI loops, the HAM3 ISI doesn't see the H3 dip at ~6.5hz develop into a nasty high q zero; the HAM3 HEPI horizontal DoF controllers are 2hz ugf non-generic.

Hugo has produced new generic controllers with the 2hz ugf, I'll upload those as soon as the machine is available.

Restarted data concentrator at 16:20:50 to clear the bad DAQ status for the h1omc model which was modified Sept. 9.  

The h1nds1 daqd process did not restart itself, and had to be manually started with monit.

08:00 (carryover) LVEA is LASER HAZARD

09:30 Cris at -End-X

09:59 Kyle at End-X

10:14 Karen at End-Y

10:29 Reset HEPI watchdog accumulators for BS and ITMX. This had not been done as part of the Tuesday weekly routine.

10:32 Kyle back from End-X

10:33 Jason out o ITMY OpLev

10:36 Karen leaving end-Y

10:41 Travis out to LVEA to worlk on Quad Test Stand

11:50 Kyle out by HAM6

12:43 HEPI end-Y threw an alarm for pump differential pressure

12:49 Jim to restart Seismic models on HAMs 4 and 5

14:24 Corey out to East bay to look for parts

14:50 Corey out of LVEA

15:16 M Landry into LVEA to walk around in prep for Saturday Tour

The DAC enable status of the h1iopseih45 model went bad at 14:16:44 PDT on Sept. 11.  This required all models to be killed, then the IOP model to be restarted, followed by starting all the user models again.  At the time the DAC enable went bad, the IOP state word also reported a FE, Timing, and ADC error, which were cleared leaving the DAC enable error which requires a model restart to clear.

Centering: Done.

I continued the POP sled centering this morning and now it's good (see yesterday's entry on the same subject: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=13890).

I ended up moving both PIT and YAW by large amounts. Though the picomotor count is not realiable as a reference (because it has hysterisis and because the software sometimes skips the counting for some reason), just to see how much I moved, I show those numbers anyway.

With the whitening gain of 45dB, QPDA and QPDB SUM (raw counts) were 1595 and 1463 counts on average for a straight shot beam, while we expect 1540 for both assuming 10W through IMC (it should be more like 8W in reality), so the measurement is somewhat larger than expectation but is still quite consistent with expectation.

Whitening gain: Changed to 12dB (from 45dB)

After the above adjustment was done, the whitening gain was lowered by 33dB so that the QPDs wouldn't rail when the PRC is locked to the carrier, and dark offsets were remeasured and set. The nominal whitening gain now is 12dB.

"toW" filters in the input are now "uW"

"toW" filters in FM10 of the input are redone such that the output is the power the diode receives in micro Watts when the whitening gain is 0dB, the filter name was changed to "uW", and I put "-12dB" filter in FM9. This way, when you change the whitening gain all you need to do is to change FM9 or add other fixed gains in FM5-8.

Anyway, I used the following calculation:

Responsivity of the diode is 0.8 A/W. Transimpedance is 1 kOhm (https://dcc.ligo.org/LIGO-D1001974). ADC is 2^15 [counts/volt]. There's no factor of 2 (single ended signal V is sent out as +-V differential, but it's converted back to V at the receiving end).

So the entire chain has 0.8A/W * 1 kOhm * 2^15 cts/V = 2.621E7 cts/W = 26.21 cts/uW.

"uW" filter is just a gain of 1/26.21 = 0.038. (FYI, "toW" filter used to have a gain of 0.0056, don't know why.)

With the straight shot beam, and with "uW" and "-12dB" on while the whitening gain is 12dB, POPA and POPB SUM are 0.34 and 0.31 uW respectively. OTOH 10W(MC)*3%(PRM)*229ppm(PR2)*10%(90:10)*1/2=0.34uW, so it's reasonable.

Saw that these HEPIs were tripped.  Greened watchedogs, Guardian (bless you) did the work.  Saw there was no drive at DAC OUTPUT (right end of medm.)   CDS overview shows red under WD of H1IOPSEIH45:  this subscreen (H1IOPSEIH45_GDC_TP) shows red under DK.  Strangely now though, even with HEPI tripped, the H1IOPSEIH45 is the only red on the CDS overview screen.  The H1HPI & ISIs show green for HAM4 & 5.  Something is not consistant.  I just greened up the CDS overview for HAM6 HPI by untriggering the HPI watchdog.  I'm sure Dave has this wired reasonably, but maybe too complexly for me to untangle.

Okay, maybe unraveled a bit for me.  I just tripped the HAM6 HEPI again but the CDS overview did not go red until the DACKILL went red on the HPI Watchdog screen; just confirmed this while untripping .  The HAM4 & 5 DACKILLs (on the ISI screens) are not red.

Bottom line--HAM 4 & 5 are not under SEI control due to an unresetable DK like HAM2 & 3.

I installed a calibration filter (just a scaler) in POP_A, POPAIR_A, REFL_A, REFLAIR_A and ASAIR_A in order to calibrate them into either mW or uW to do some meaningful science.

I used the following convsersion: [cnts/W] = 0.76 [A/W] x 200 [Ohm] x 2¹⁶ / 40 [cnts/V]

LVEA is LASER HAZARD

Op Lev - ongoing investigation of ITMY OpLev 

TCS Install - no one present to report

Vacuum - No one present to report

P King - would like to pull cables for ISS. FE LASER watchdog tripped last night. Comments made about aginf NPRO. misc: H1 LASER 'accepted' about 3 weeks ago.

F Raab - suggested some sort of "dashboard" as a visual means to monitor which (sub)systems have passed acceptance testing

Seismic - reported that excess moin in ITMX has been remedied and there will be further investigations into the reason(s) There was a discussion about the 'global' condition of HEPI/ISI world akin o the aforementioned "dashboard"

Commissioning-  Keita will be working on getting the SLED QPDs aligned in the morning and then working on the PRMI in the afternoon to coordinate his activities with the ongoing Seismic testing/investigations.

K. Venkateswara

At UWash, I have built a simple turn-table with two 1.0 kg brass weights controlled by a stepper motor. The angular position of the table is controlled in a 0-90 degree range by a 0-5 V signal applied to the stepper motor controller (consisting of an Adafruit Shield on top of an Arduino Uno). Pictures are shown on page 1 of the attached pdf. The gears and support structure were laser-cut out of acrylic (with our very own 400-W CO2 laser-cutter).

When placed under the beam-balance, the brass weights apply a purely gravitational torque on the balance depending on the angular position. To damp the balance, I take the autocollimator output (angular position of the beam-balance), differentiate it once and band-pass between 3-33 mHz and use it as the control signal after appropriate gaining. The result is shown on page 2.

This setup should work very well with the BRS at ETMX. We could have the damping controlled by the Front-End so that if the beam-balance does get rung up by people in the vicinity it could be remotely damped and the damping turned off once the amplitude is small. Preliminary results indicate that it could even be left on permanently with Q set to 50-100.

model restarts logged for Thu 11/Sep/2014
2014_09_11 00:45 h1fw0
2014_09_11 01:02 h1fw0
2014_09_11 13:12 h1fw0
2014_09_11 14:39 h1fw0
2014_09_11 16:21 h1fw0

four unexpected restarts of h1fw0, h1ldasgw0 was rebooted to resolve the instability.

Did various tests. No dramatic results yet. Here is just a brief summary:

• I could lock PRMI without using the variable finesse technique on the carrier. I used the same settings as the sideband locking except for the sign of the PRCL control
• Moved the spot position upward on PR3 and ITMX by an inch or so while keeping the same spot on PRM and PR2.
  • At this point, POPAIR does not come out to ISCT1 at all. I could not measure the recycling gain, but the BS spot looked dimmer.
  • Though, this definitely reduced the scattering from PR3.
• Moved IM4 angle such that the PR2 spot goes up. This operation seemed quite effective to increase the intracavity power.
  • This is true even for the PRX configuration. Some clipping losses ?
• Tried focusing the PR2 GigE on the infrared objects. I cloud get a better focus. But the PR2 python camera process had been frozen for some reason and therefore I could not get a sharp image.
  • This also happened to the PR3 GigE. They need to be fixed in the daytime tomorrow.
• I implemented a oplev damping loop in the bottom stage of PR3 to supress 0.7 Hz motion.
• The spot motion on the BS seemed better tonight presumably because of the better ITMX ISI and PR3 oplev damping loop.
• The highest build up today was almost the same as the recent best i.e. 3000 counts in POPAIR_A_LF (corresponding to a recycling gain of 15),
• We need to calibrate the ASAIR_A_LF.

J. Kissel, R. Adhikari

In attempts to investigate the long-term, sawtooth drift seen in the H1 SUS ITMY's optical lever (see LHO aLOG 13863), Rana and I went out nudged and poked things on the transmitter/ laser launcher side of things. I attach a time series of the optical lever signal over 4 hours, starting at 2014-09-11 2349UTC, or roughly 4:50p local, and explain the timeline below.
- At around 5:44p local (marked in mustard yellow), Rana gave the pylon a couple of hefty nudges to see if anything was loose. This clearly shifted the pylon in yaw, but had no affect on the sawtooth.
- For the next 10 minutes (between yellow and black), we wandered around the LVEA locking for wrenches to tighten down the nuts and bolts connecting the pylon to the concrete. 
- Having found some, we then cranked on all accessible bolts (marked in black). This moved the pylon in yaw some more. 
- Realizing we needed to open the hood to get it realigned (we got no action out of moving the ITM around), we looked for some allen keys (between orange and black). 
- During this time, you could convince yourself that the sawtooth remained. 
- Once we got back, we opened the lid, which pushed the beam off the edge of the QPD (marked in red). 
- We then unlocked the pitch and yaw adjustment micrometers, and re-centered the beam on the ITM (marked in blue). 
- After recovering the transmitter, Rana went to Daniel's for dinner, and I came back into the control room.
- At around 7:25p local, Kiwamu misaligns ITMY to work on PRX cavity locking, so the beam falls off the QPD again (marked in green).
- At 8:10p local, he realigns ITMY into a Michelson configuration -- and voila! sawtooth has reduced.

The message: I think this means that the problem lies in the QPD. Maybe one of the quadrants in bad, such that depending on the location of the spot on the QPD this drift is more or less prominent. I'll try walking the beam around the QPD for the next hour or so before people come back from dinner to see if I can nail down the problematic quadrant.

H. Radkins, J. Warner, S. Biscans, J. Kissel

Here's a prioritized list of things the LHO SEI Team + Seb intends to tackle (or start tackling) over the next 10 days or so.

(1) Fix problems with ITMX ST1 [[DONE -- aLOG pending shortly]]

(2) (a) Add control of sensor gain and whitening settings to matlab transfer function scripts to ensure they're *always* in the right configuration. 
    (b) Fix blend filter design plots in commissioning scripts to show the blend design MUCH better than it currently does.

(3) Finish commissioning HAM4 and HAM5 ISIs and HEPIs

(4) Support commissioning efforts with "spot" improvements, if possible.

(5) Resurrect Fabrice's Standardized Commissioning Steps list

(6) Use (5) to assess all chambers, to see where we are -- at least with the "fixed" stuff

(7) Gather "current performance" plots for all chambers

(8) Gather HAM2 and HAM3 in-vac, HEPI unlocked, floating, with fluid TFs and HEPI-Position-controlled ISI TFs to help investigation with HAM4 and HAM5 results

(9) Resurrect plant comparison script and use it to compare in-vac transfer functions between HAM and BSC ISIs

(10) Teach Jim and Hugh how to commission sensor correction / feed forward.

(11) Play with Beam Rotation Sensor at EX -- try to get some performance improvements

(12) Think hard about HAM and BSC performance models.

J. Kissel, J. Rollins, S. Dwyer, A. Staley

While Sheila and Alexa began to lock PRMI on carrier, the HAM2 and HAM3 HEPI and ISIs tripped for an unknown reason. We'll leave this to people offline to figure out what happened. See attached actuator trip plots from the ISIs.