This morning we disconnected all DC power to PEM electronics (SEIS, TILT, MAG, MIC ect) and connected them to the dedicated PEM power supplies. This should start cleaning up some of the clutter in the VEA, example power supplies sitting on the floor used for temporary power. Everything should be up and running, but let me know if we missed something.

[Sudarshan, Gabriele]

To understand why intensity noise was worse than usual, we had a look again at the beam dumps we installed yesterday on the two beam coming out into IOT2R. 

After yesterday's realignment of the main beam, the two dumps were no more in a good position. To be more precise: the two beams coming into the enclosure are very close to the edge of the periscope upper mirror; one of the beams is hitting the bottom mirror in a reasonable position but was partially missing the beam dump; the other beam was hitting the edge of the mirror and the mount. Therefore, we moved the first beam dump to a better position, and we dumped the second beam before it hits the periscope bottom mirror. See attached picture

This improved the intensity noise, but we can still see a bit of 18 Hz peak. 

Intensity noise was very high this morning, see the red trace in the first attached plot. It started to be like that yesterday night, during some of the locking tests. After some investigations, it turned out to be due to the LSC correction sent to MC2 and generated by the ALS. After switching it off, intensity noise returned to reasonable values, even though a bit larger than usual, inicating a not optimal alignment of the IMC.

Another pecualir thing is that yesterday night, while IM4 ws moved, the power on IM4_TRANS changed as well. This is a bit unexpected...

Looked like commissioners were still working on the alignments so I held off on doing similar to WHAM3.  So, I went to the ITMY which also needed some matrices corrections.  These corrections required new controllers so I just went with Hugo's standard controllers and some mods to those, see 15112.

I brought down the HEPI at ~0805pst, the ISI watchdogs tripped very soon after.  About 0813 I loaded the new matrices and attempted to restart the HEPI after adjusting the X dof Target Location.  The RZ loaction did not change as the matrix errors I'm correcting are amplitudes in X & Y and the output matrix which was all 1s.  Did you notice I forgot to mention loading the new controllers (required with changed matrices?)  Well I did forget them, so then I prepared and loaded the new controllers and tried again.  Okay, not so good...the vertical dofs are tripping quickly when the boosts turn on.  Well, if you remember from my yesterday's alog, I elected to leave the vertical controllers at 5hz UGF.  So I lowered them to 2hz like all the horizontals (I hadn't actually tried the horizontals yet, but I later did and they were fine.)  Still the verticals blow up quickly when the boost is engaged.  So, I continued and reduced the zero of the boost from 1.0 to 0.7hz as I did with the horizontal dofs.  But, still no luck so I lowered them to 0.5hz and again no good.  Alright, I tried the horizontals and they worked, I did the verticals manually and they are fine without the boosts.

Next I set up to do an open loop, this would reveal if my controller's matrices did not match my installed matrices.  Well, the boosts would not engage at all for Z RY or VP!  We attempted all sorts of things like resaving the file from foton, confirming the turn on method, comparing the boosts, putting the boost in another module (where it did turn on.)  Finally, restarted the model, and HEPI isolated first attempt (3 hours later!)

So, the new matrices and new controllers work--why did these filter modules stop engaging properly and sending some wacko spike into the output--they would not have done any harm if they actually weren't doing anything?  I thought about reverting the controllers back to where I started to see if at first it was actually my boosts but the the shape changes were actually quite minor: the gain peaking dropped from less than 3 to less than 2, and phase margin went from ~30 to ~50 degrees.  Too little time so I didn't change them back.  So unless my controllers were very bad to start and the repeated loading of fotons and tripping the watchdogs did something, the first attempt with the non-updated controllers must have done something to the filter module/model, or, it was a problem waiting to happen.

I noticed that the Guardian was restoring the RX & RY Target Location.  I'm confused with that.  I thought we were only restoring RZ everywhere, with Pitch at the ends, and X on ITMY (initial alignment.)  I'll research the history and maybe I'll learn something but again, I did not think we were restoring these.  It might make sense to do so as these are the tilting of the platforms but that is another issue.

I'll put an updated image of the controllers in shortly.

Updated safe.snap and latest foton file filed in the svn.

[Sudarshan, Gabriele]

• Changed the ISS second loop medm screen, to include the correct functionalities to contrl the second loop
• Modified the ISS model to change the channels written to frames:
  • The first loop signals have changed: PDA_OUT and PDB_OUT are no more written. Instead we write PDA_REL_OUT and PDB_REL_OUT which are calibrated in units of RIN. They are both written to science frames, at 16kHz
  • Added both second loop signals SECONDLOOP_SUM14_REL_OUT and SECONDLOOP_SUM58_REL_OUT to science frames (only SUM14 was previously written). Reduced the sampling rate to 16kHz
  • Added the second loop QPD signals to the commissioning frames: SECONDLOOP_QPD_PIT_OUT, SECONDLOOP_QPD_YAW_OUT and SECONDLOOP_QPD_SUM_OUT, al at 2kHz

Model has been recompiled and restarted.

For Ubuntu workstations, a new version of TDS tools have been installed.  Following a complaint that ezsfft was failing, it was determined that the tool needed to be recompiled since libraries ezsfft depends on have been updated.

Note that the documentation states that ezsfft is obsolete, tdsdmd should be used instead.

The ezsfft no longer core dumps, but it doesn't seem to work, either.  The tdsdmd tool does appear to work, so it should be used instead,

The ezlockin script has been changed to use tdsdmd and tdssine instead of ezsfft and ezsine.  I have no idea if the script still works, there's no test case for regression testing.

This will affect all users -

The user environment setup scripts have been changed to include some common aliases that may be useful to users. 

alias ll='ls -alF'
alias la='ls -A'
alias l='ls -CF'

alias target="cd /opt/rtcds/lho/h1/target/"
alias t="cd /opt/rtcds/lho/h1/target"
alias chans="cd /opt/rtcds/lho/h1/chans"
alias h1="cd /opt/rtcds/lho/h1"
alias userapps="cd /opt/rtcds/userapps/release"

alias latest="ls -alt|head"

alias scripts='cd /ligo/lho/scripts'
alias data='cd /ligo/lho/h1/data'
alias medmdir='cd /opt/rtcds/lho/h1/medm'
(there's more than these...)

If an individual user wishes to redefine one of these aliases, they can do so by editing the ".bashrc" file in their home directory to include a different alias command AFTER the line "source /ligo/cdscfg/stdsetup.sh"

A complete list of aliases can be found by entering the "alias" command with no argument (in a terminal window, of course).

I have also changed the setup scripts to recognize a different operating system, but this should not affect any users and is in place for testing candidates for the next control room computer OS.

I've run the latest updates on all the CDS workstations and rebooted them as part of Tues maintenance.  (opsws6,9,10 are pending reboots as they were in use this morning.)

Add 125ml water to Diode room crystal chiller

The attached plot shows a trend of 60 days of beam spot position on the IMC WFS. Excluding two manual re-centerings of the beam (I'm sure about the last one, since I did it) the beam is not moving significantly on the WFS. The peak to peak motion is at most 0.1-0.2 in units of QPD normalized signal, which corresponds to 0.06-0.12 fraction of beam radius.

The position looks quite stable over long periods.

model restarts logged for Mon 17/Nov/2014
2014_11_17 14:27 h1fw1

one unexpected restart

(Sheila, Evan, Keita, Nic, Kiwamu, Alexa)

We locked the IR to the x-arm and adjusted PR3 until we achieved the good IM4 alignment specificed in alog 15109. We adusted the HAM3 picometers to restore the ALS green trans beam on ISCT1; I used the camera reference position that we had previously found (alog 15072) and ensured a high build up in TRX. We then aligned MICH on the dark fringe and PRM using PRX lock. Not surprisingly, we had to move PRM a lot.  SRM was also aligned, with SR2 and SR3 in the old configuration. Attached is a screen shot with the current alignment values. The POP sled was aligned as noted in Keita's alog 15116.

We were able to lock PRMI on the sideband, and acheived 260 cnts build up. Our best build up had been between 260-399 cnts as seen by a trend Keita had taken over the span of 3 weeks. We feel okay about our current build up. 

Sheila and Evan marked a new IM4 trans beam on the wall in the LVEA. It seemed the beam hadn't moved all that much from the old position (from June); maybe a few millimeters.

We adjusted the ALS alignment on ISCT1; we got 0 dBm for COMM beatnote, and 6 dBm for DIFF beanote.

ALS DIFF locked right away. The UGF was 7 Hz, with 70 deg phase margin. The in loop RMS was 0.2e-3 um/srtHz at 0.1Hz. This was with feedback to ETMX only.  We then tried feeding back to both ETMX and ETMY L1 stage with Jeff's new EY L1 L2P filters engaged (FM6, FM7); however this did not work. The L2P filters output a huge value 1e+20 and we saturated the DAC immediatly. FM7 has a step response of 10^18 ! Also, are we supposed to leave Arnuads invP2P filter engaged? We must have rung up a mode around 10 Hz. Nic and Kwamu fixed this (see their alog 15118).

We locked DRMI 1f with the ASC wfs engaged. POPAIR18 measured 343cnts, and ASAIR90 measured 5731. It appeared to be the best DRMI "moment of [Sheila's] life." DRM1 1f lock time Nov 18, 2014 6:07 UTC. We transitioned to 3f flawlessly at ~ Nov 18, 2014 6:12 UTC. We lost lock at Nov 18, 2014 6:14 UTC.

Then we tried locking DRMI with the arms 500 Hz IR off resonance. At first, the DRMI alignment did not look as good; when we engaged the wfs the build up increased dramatically but we would lose lock when the build up got high. We deduced that the gain of the loops had to decrease with the precense of the arms. We reduced MICH gain from 5 to 4 to obtain a 15 Hz UGF. PRCL we reduced from 22 to 11. At some point the alignment looked good and the lock was stable for a bit, but we lost lock trying to measure the SRCL loop gain.  We got tired...

A second round of testing on the all-metal 3IFO QUAD unit Q7 is attached.  After we saw a few cross coupling terms and struggled with coherence in the prior measurement set, we made a few adjustments to the QUAD mechanics.  However, readjusting the lacing cabling and retuning the sensor mounting tablecloth seemed to not help much.  There is still L and R bleeding into P on the reaction chain.  We were able to improve the coherence by building a fort around the test stand however.  The main chain looks to be in pretty good shape though.

The first attachement below is of Q7 with damping on and off.

J. Kissel

I've measured new transfer functions necessary redesign of the H1SUSETMY UIM (L1) DRIVEALIGN frequency-dependent decoupling filters for L2P and L2Y. For the impatient, the last page of the last attachement shows a comparison between the proposed new design and the old, currently installed / in-use design. I have *not* installed this filter because I'd like to discuss the results with commissioners tomorrow morning (and it'll take me some time to resurrect quack to get these installed). In fact, this may argue for us to indeed just copy over ETMX's filter.

Details:
-----------------------------------------
I attach the measurement results (see 2014-11-13_H1SUSETMY_L1_drivealignfilters_rawdata.pdf), but the raw templates can be found here:

/ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMY/SAGL1/Results/Data/
2014-11-13_H1SUSETMY_L1_L2PY_WhiteNoise_ReactionChainTest.xml
2014-11-13_H1SUSETMY_L1_L2PY_WhiteNoise.xml
2014-11-13_H1SUSETMY_L1_P2PY_WhiteNoise.xml
2014-11-13_H1SUSETMY_L1_Y2PY_WhiteNoise.xml

Not that I drove through the TEST filter banks (instead of having to turn off all the existing filters in the LOCK and DRIVEALIGN banks), and made sure that optical lever damping was OFF, and local damping was the LLO design as described in LHO aLOG 14959.

I focus this entry solely on L2P, but the data exists for an L2Y filter if ever needed. in the first four pages, Pink curves are the current measurement, and black curves are what were used in the original design of the previous filter by Arnaud (see LHO aLOG 11832). The encouraging fact is that the data supports exactly what we'd model from the change in damping loop filter design (see green traces on pg 5 of first attachement to LHO aLOG 14959). As an aside -- just because Betsy made me think of it while chasing down slider values -- what effect does reaction chain alignment have on these off-diagonal, lower-stage transfer functions? One might guess that if the L2P cross-coupling isn't something fundamental but a result of dirt alignment affects between the coils on the reaction chain and the magnets on the main, then one would see a change in the L2P transfer function with different alignments of the reaction chain. The good news is that is doesn't have any effect -- see the last page of 2014-11-13_H1SUSETMY_L1_drivealignfilters_rawdata.pdf. I compare the same transfer function for 4 different reaction chain alignments. They still have the old dead-reckoned calibration factors installed, so we know they're not exactly [urads] but close enough for the scale of these offsets used; they use up about 1/2 the DAC range.

As far as the design goes, I used the same transfer function fitting routine and filter generation software suite that (I think) Arnaud used, namely the function
/ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/FilterDesign/Scripts/Length2Angle_decoupling.m 
which is essentially a wrapper around the function,
/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/happyVectfit.m 
which Keita's wrapper around the function,
/ligo/svncommon/SusSVN/sus/trunk/Common/MatlabTools/vectfit3.m
All tweaking of input parameters to the fitting routine, and plots were made using the overarching script
/ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMY/SAGL1/design_H1SUSETMY_L1_L2P_20141113.m

Notable key additions to the design software -- a computation of the final filter's impulse response, as well as a comparison to the previous design.

As I know Arnaud had struggled, I struggled to find a fit with which I was really happy, namely because we all *know* that the L2P transfer function should fall off as some large power of frequency (again, see the models of these TFs on pg 5 of LHO aLOG 14959), but I can't find a set of parameters happyVectFit / vectfit3.m that allows for such a roll-off at high frequency. Indeed, the height of the final flat part of the L2P fit transfer function directly determines the high-frequency gain of the decoupling filter, and directly impacts the impulse response time. I settled on a filter that does a poor job at reproducing the > 2 [Hz] behavior of the L2P measurement, BUT I think it's OK because
(a) the small magnitude of the high-frequency causes a significant drop in impulse response time, and
(b) At the UIM, we're typically driving below 2 [Hz] -- especially if the crossover remains at 0.9 [Hz] as quoted in LHO aLOG 15025, so the accuracy of inversion is not so critical. Though I didn't find any design aLOGs, this seems to have been the philosophy behind the ETMX UIM L2P filter because it ends up looking strikingly similar.
I should say also that having to tune the uncertainty tolerance, the order (i.e. number of poles) in the filter, the tolerance for when to throw out adjacent poles and zeros, the frequency range over which to fit -- all free parameters into happyVectFit.m -- as one has to do to get what one wants in the end really destroys the advantage of automating the fitting process. If only there was a better way...