Chris ran the swiffer in the Diode Room this morning for the first time in 8 months. Will try to make cleaning more regular.

Earlier tonight Alexa made some measurements of IMC transfer functions to for matching with her model, and I worked on the slow feedback to the ETM top mass. (alog about that coming in the morning, in short the L2P decoupling has helped)

Now I've made some measurements similar to what ALexa and I did on Monday night (alog 10668) of the linear coupling from the test mass angles to the out of loop frequency noise sensor (the normalized refl PDH).  This time I dithered the PZTs on ISCEX, and measured the spectrum of the normalized PDH and the green QPDs on the input beam on the TMS table.  I haven't calibrated the QPDs, or measured the loop gain, but these are verry slow loops and I dither the PZTs at 5Hz so that should not matter. By dithering each PZT in both pitch and yaw, and finding the peak in the spectrum of both QPDs each time, we get 2 measurements of the coupling from each QPD to frequency noise.

As you can see the measurements made with different PZTs aren't always consistent.  Using these and measured spectra of the QPDs, we can make the projection of the linearly coupled  noise from input beam pointing to ALS frequency noise, it is not a significant contribution (below 100Hz) based on any of these measurements. At around 100 Hz these projections seem to explain the noise, I believe this is just the noise of the QPDs, but will check in the morning. 

I also checked the linear coupling from the ETM pitch to frequency noise, to see how much it changes with alignment. I measured 424Hz/urad, moved the ETM by 0.1urad, measured 1.12kHz/urad, tried to move it back to the original spot and measured 2.03kHz/urad.  Then I tweaked up both pitch and yaw on the ITM and ETM to try to maximize the green transmission, and got 3.2kHz/urad. So we can change the linear coupling by adjusting the alingment; by hand I only seem to make it worse but hopefully the WFS will do better.

I am leaving the green arm locked, and the guardian running the ALS COMM handoff, so hopefully the IR will be resonanting in the arm some part of the night.

h1pemmy is finally up and working.  The first problem relatively easily found was a bad ADC card, which was swapped early on after it was seen to generate 'channel hopping' errors to dmesg.  Said card has been marked as bad (it was probably pulled from somewhere else, but not actually labelled as bad which led to it's later unfortunate re-installation).  The second issue was that after replacing the ADC card the duotone signal was not appearing on CH31 (numbered from 0).  This led to a number of time consuming component swaps to eventually find that the cause was a bad cable from the internal 16 channel Contec card to the IO chassis backplane.  I could verify with the IO chassis powered up, but the front end computer off, that the duotone signal was present on the correct pin of the cable feeding the ADC.  After boot/code initialization, the duotone input was switched off by the relay on the adapter board, and the last channel of the AA chassis would then feed the ADC (verified by injecting a signal through the AA chassis).  I could also verify the relay control voltage with the Duotone0_select testpoint on the backplane.  The code is (in it's present form, in theory) hard coded to never activate this relay, so seeing 5V here is not right.  The cable itself is mis-crimped, such that pins 1/20, 2/21, ... , 18/37 are shorted together, with pin 19 not connected at the male/Contec side of the cable, a fact not immediately obvious in the back of a dark rack, but more so once exposed to the light...  The moral of this tale is to double check the internal 37 pin cable that controls the backplane if the duotone signal seems to go missing between the testpoint on the board and the ADC sometime after boot, there may be more of these floating around.

Offending Y2P peak between 1 and 2Hz (pink) was removed after a new decoupling filter was put in place (green).

In the H1:SUS-ETMX_L2_DRIVEALIGN_Y2P filter, I put the same invP2P filter in FM1 as in the P2P path, then added a diagonalization filter ("Y2Pdiag") in FM2, and another filter that is a 3rd order elliptic BP in FM3. I didn't try to remove 0.4-0.5Hz Y2P peak, it's not great but probably good enough.

Thomas started work on an Operator Overview screen.  This screen has a graphic of H1 with all of its chambers.  For each chamber, we have buttons to easily & directly open HEPI, SEI, & SUS screens.  The buttons are also colored such that they indicate whether Watchdogs are GREEN or RED.  So for quick glances, this medm can give you an idea of ALL WATCHDOGS.

This is a living screen, and we plan to add more features (Guardian, "Measurement In Progress", etc.).  This medm currently resides at: 

/opt/rtcds/userapps/release/sys/h1/medm

We currently have this medm is now an FOM & currently on our video1 Wall Monitor.  The CDS SUS Overview also shares this FOM, but we may remove that screen since that screen is sort of redundant (or it will be once we get all SUS screens on the Ops Overview screen).

TF is setup on the workstation with a 2.5 hour delay, to allow for PCAL work. Lucky number 3.

.......LVEA:  Laser SAFE..............EY:  Laser SAFE.........EX:  Laser HAZARD.......

A major activity today was the installation of the Spool at EY, installation of viewports on the spool, and then getting PCal pylons staged into position.  Other activities are:

• Jeff:  Dust Monitor #1 in LVEA is in HAM5 cleanroom--had INVALID alarms most of the day, so it is currently offline to charge overnight.
• JAX checking for shorted cable at ISCTEY
• Justin heading to EY & EX to check stuff (900-945)
• Betsy:  working at ITM build area most of the day
• Mitch West Bay Clean-up (925-955)
• EY #1 dust monitor is at the spool clean room for spool installation, it had a blown fuse and it was replaced, and should now be online
• Filiberto:  HAM4 cable pulling
• Jax:  heading backto ey
• Cyrus:  working on PEM rack at MY
• gerardo:  ofi work in H2 psl room
• Jeff/Andres:  Working on SR3.  Running TFs now
• SEI Measurements at EY 2-4pm?  But HEPI tripped during measurement
• Travis:  searching for weld panels at end stations
• Justin & I (with help from Arnaud) followed Sebastian's instruction for bringing back a few BSC ISIs from Watchdog Trips

End-Y - The dust monitor in the spool cleanroom (#2) at End-Y failed with a low battery message. Filiberto replaced a blown fuse in the network junction box. The dust monitor appears to be working at this time. The dust monitor for the BSC10 chamber (#1) is charging and will be replaced in the morning. There is a temporary handheld unit in the chamber cleanroom. 

HAM5 Cleanroom – Getting communications errors on the dust monitor in the HAM5 cleanroom. Filiberto found low voltage on this unit. It is shut down for charging overnight. I will bring it back on line in the morning.     

I updated Simulink noise budget model to incorporate balanced BS/PRM actuator.
Updates made since last alog (#10441) are;

• ISCINF, (M2|M1)_LOCK filters are added (see alog #10559)
• PRM suspension model correction factor is added (see alog #10674)
• PRMI sensing matrix measured is added (see alog #10725)

PRMI sensing matrix I used is;
                PRCL    MICH
REFLAIR 45 I    4.8e5   1.5e4
REFLAIR 45 Q    3.9e3   -2.6e4  W/m

Some plots from NB model are attached. Data I used is taken from Mar 12, 12:43:00 UTC for 2048 seconds, when PRMI is sideband locked with REFLAIR45.

OLTF_MICH_1078663396.png: MICH OLTF. The magnitude from the model is higher than the measured by ~40 %. This means that there are some errors in the sensing matrix measurement. We have sensor/actuator calibration error of ~10%. Also, there was a power drop in the cavity build up (POP18) by ~10%. However, these errors don't explain the disagreement between the model and measurement. We need more investigaton on this. (There was is a suspision about the factor of sqrt(2) in BS, but I've checked that)

OLTF_PRCL_1078663396.png: PRCL OLTF. The model and measurement agrees within 10%. Also, phase looks reasonable (compare the OLTF before output matrix diagonalization in alog #10441; we had a dip).

PRCLtoMICH_1078663396.png, MICHtoPRCL_1078663396.png: Measured coupling between MICH loop and PRCL loop (TF from H1:LSC-MICH_EXC to H1:LSC-PRCL_IN1 or vice versa). Compared with the same measurement done before output matrix diagonalization, coupling is at least factor of 2 less (see alog #10481). Model explains some features qualitatively.

NB_MICH_1078663396.png, NB_PRCL_1078663396.png: Noise budget for MICH and PRCL loop. Note that seismic noise is not real (copied from LLO model).

LASER

• PSL Laser is ON & Power is 28.5W (should be 30W; attached is 400-day trend where power starts at ~33W and drifts down to current value)
• WD ACTIVE
• PSL SYSSTAT.adl is ALL GREEN (except VB Program)

PMC

• Only locked for last 1 day 15hrs (should be on order of days/weeks)
• Reflected Power is 12% of Transmitted (should be 10% or less)

FSS

• RefCav only locked for last 8hrs (should be order of days/weeks)
• Alignment looks a little off in pitch on video
• Trans PD is 0.888 V (should be atleast 0.9V)

ISS

• Diffracted Power 13.6%
• Last Saturation Event was when PMC was relocked 1 day 15hrs ago.

model restarts logged for Wed 12/Mar/2014
2014_03_12 16:09 h1ioppemmy
2014_03_12 16:28 h1ioppemmy
2014_03_12 16:28 h1pemmy
2014_03_12 21:02 h1fw1

All expected except for the h1fw1 restart.

Yesterday, we found that the reaction chain of ETMY quad was rubbing, so Betsy and Travis made some adjustements and a round of TF was ran overnight. The results are now clean, meaning the suspension is free of rubbing for both chains. This will be our official phase 3a set of transfer functions.

The first attachement shows the transfer functions for the 6 DOF of the main chain and the second attachement for the reaction chain. TF have their peaks matching very well with the model, except T DOF of the reaction that has an extra resonance at 0.86Hz which is a roll mode. (and as usual the reaction chain pitch which differs because of added stiffnes from cables which couples into the L DOF).

I added to the plots the phase as well as the ratio between model and measurement.

I attach here three plots showing the Local and Cartesian positions for the ETMY HEPI for the last 72 hours.  I conclude that, at least in this instance, the high frequency excitations (100-1000Hz) which ran this morning, destresses the platform and exhibits strains of significant magnitude.

The first plot is the four vertical Inductive Position Sensors showing the zeroing of the IPS after Alignment approval Tuesday afternoon. When Mitchell pulls ACB elements Wednesday Morning, there is vertical shift of 100s of nm; as we expected, not too much to worry about.  Toward the end of the plot, the start of TFs beginning at 500 to 1000Hz and then continuing with 100to 500Hz as well shows small steps.

The second plot however shows the four horizontal IPS and much larger steps in the IPS readouts at the start of the TFs.  The third plot are the trends of the Cartesian channels.  The Wednesday AM Matrix changes I made are very insignificant but not so the horizontal shifts from the TFs.  The 0.3mm translations of X & Y are ignorable but the Rz of -15urads may not be. With Jason's alignment of ETMY indicating a 20urad CCW error, and if we've all got our signs correct, the -15urads should actually put us closer to zero error.

Notice that the H2 IPS had the largest shift.  I attempt to push it back and was successful with a 1000ct local offset but it went back as soon as I removed the offset.  In the last plot attached you can see all the position senors responding to the stopping of the excitations this morning and then to  the offset and all pretty much returning to their previous values when the offset is removed.

So I would suggest that a destressing exercize of the HEPI may be a valuable step in the alignment process and of course an explicit zeroing (or at least a logging) of the IPS value are in order right after alignment, something we haven't always done.  This also stresses the importance of getting the posirtion loops turned on.

• Y Axis Position (longitudinal): 3,999,455.7 mm
  • Target: 3,999,455.4 mm
  • Error: +0.3 mm
  • Tolerance: ±3.0 mm
• X Axis Position (lateral): -199.97 mm
  • Target: -200.0 mm
  • Error: +0.03 mm
  • Tolerance: ±1.0 mm
• Z Axis Position (vertical): -79.6 mm
  • Target: -80.0 mm
  • Error: +0.4 mm
  • Tolerance: ±1.0 mm
• Pitch: 665 µrad down
  • Target: 639 µrad down
  • Error: 26 µrad
  • Tolerance: ±50 µrad
• Yaw: 20 µrad CCW
  • Target: 0 µrad
  • Error: 20 µrad
  • Tolerance: ±50 µrad

ERMy (set parallel with respect to the ETMy AR surface.  Error numbers are reported from this desired parallelism)

• Pitch Error: 860 µrad down
  • Tolerance: ±1.47 mrad
  • Actual Pitch: 2.86 mrad down [ETMy pitch (665 µrad) + ETMy wedge (1.33 mrad) + ERMy pitch error (860 µrad)]
• Yaw Error: 340 µrad CW
  • Tolerance: ±1.47 mrad
  • Actual Yaw: 320 µrad CW

ACB

• Lateral Error: -0.6 mm
  • Tolerance: ±2.0 mm
• Vertical Error: -0.9 mm
  • Tolerance: ±2.0 mm

All IAS equipment has been removed from the spool area and the spool is being installed this morning.

Cranework is beginning at EY for Spool Work (involves moving IAS table out of way, inserting spool, etc.).  Bubba noted the Dust Monitor was inoperative & Jeff B. will be heading out there to get their Dust Monitor back online.

We found that the BS ISI had been tripped. We untripped it with stage 1 isolated at level with the Tcrappy blend filter.

Stefan, Yuta, Kiwamu

We have measured the length sensing matrix in the sideband locked PRMI. The data is now under analysis and will be posted later.

Also since we now know that the in-vac REFL is functional (see alog 10661), we switched the PRMI sensors from the in-air one to the in-vac one. This is a permanent change and in fact, it is already reflected in the guardian.

Preparations (adjustment of PD gains and demod phases):

After we locked the PRMI with the sidebands resonant, we re-adjusted the demod phases such that the PRCL signal is maximized in all the in-phase paths. This was done by inserting a new notch at 100 Hz both in MICH and PRCL filters and exciting PRM with an amplitude of 30000 cnts at the output side of the LSC. We used dtt to check the demod phases. The new settings are now:

• REFL_A_RF9 = 84.9 deg
• REFL_A_RF45 = 19.2 deg
• REFLAIR_A_RF9 = 90 deg
• REFLAIR_A_RF45 = 144.6 deg
• REFLAIR_B_RF27 = 91.8 deg
• REFLAIR_B_RF135 = 76.3 deg

We didn't phase the POP detectors this time as we were focusing on the REFL detectors. Also, we changed the PD gain in the digital system to make all of them identical to REFLAIR_45. This was meant to make the calibration easier. The new gain settings are now:

• REFL_A_RF9_I(Q)_GAIN = 0.252
• REFL_A_RF45_I(Q)_GAIN = 0.275
• REFLAIR_A_RF9_I(Q)_GAIN = 1.040
• REFLAIR_A_RF45_I(Q)_GAIN = 1 (because this was chosen to be the reference for everyone else)
• REFLAIR_B_RF27_I(Q)_GAIN = 0.210
• REFLAIR_B_RF135_I(Q)_GAIN = 1 (we didn't do it on this guy for some reason)

At this point, we could see all the I-phase signals beautifully overlaid on each other in the spectrum.

The measurement:

We then moved on to the measurement of the LSC sensing matrix. We continued shaking PRM with the same amplitude of 30000 cnts. We left the notches in at 100Hz to avoid surpression from the LSC control loops. Since we wanted to quickly get a result, we decided to use dtt instead of the online lockins. Monitoring the DAC of BS, PRM and PR2 suspensions we didn't observe a saturation during the measurement. Good. All the 1f detectors had a whitening gain of 0 dB while REFL_RF27 and REFL_RF135 had a whitening gain of 27 dB and 21 dB respectively. We set the bandwidth of the FFT to be 0.1 Hz and averaged it by 10 times. Note that the PRCL loops should have a UGF of about 35-ish Hz and the MICH loop should have a UGF of about 10-ish Hz. So the excitation is above the UGFs.

As for the MICH sensing matrix measurement, we tried three different excitations -- (1) excitation on the diagonalized combination of PRM and BS at 100 Hz, (2) excitation on only BS at 100 Hz, and (3) excitation on ITMs at 18 Hz. The third configuration was not really successful in a sense that we didn't see a big excitation. Also we didn't spend a long time to study the optimum excitation on ITMs this time.

In the first and second excitation configurations, we injected an excitation with an amplitude of 300 cnts above of which the BS saturated at its DAC. Since the excitation was puny, we narrowed dtt's bandwidth down to 0.01 Hz this made the coherence somewhat better.

A permanent change -- in-vac locking:

We did nothing special to switch the sensor from the in-air to in-vac. We simply set the LSC gains right. Currently REFL_A_RF45_I is for PRCL and REFL_A_RF45_Q. for MICH. We then confirmed that the in-vac detector grabbed the PRMI fringe without a problem. Also we noticed that the in-vac Q-signal contained less noise by a factor of 5-ish (actually I forgot the exact number, sorry) above 30 Hz and therefore the BS DAC should be happier now.

Additionally, we confirmed that we could still transition to the 3f diodes smoothly by the guardian.