Per WP #4422, Filiberto and Aaron have arrived at EX (11:00 AM local) to install the Trillium seismometer.  Patrick is there also investigating the dust monitor.

This morning I can see that the drip is forming at the Valve Cover and not at the Valve/Manifold seal.  The valve may still be working fine but it should be changed out and repaired.  This could be delayed if the glitches and being offline for a few hours tomorrow is untolerable but I'd prefer to get it done sooner rather than later.

Here is the list of commissioning task for the next 7-14 days:

Green team:

1. Implement optical lever feedback damping to address the mode hopping problem.
2. ETM drive diagonalization
3. Commission the red cavity lokcing signals.
4. Lock the arm cavity on red.
5. Make a mode scan of the red resonances
6. Commission the common mode hand-off including the AO path.
7. Measure difference between red and green locking offsets.
8. Commission the length feedback path to the ETM top suspension point to suppress microseism.
9. Asses the status of the reference cavity temperature controls.

Red team:

1. Mode matching measurements using ISCT1 and maybe IOT2R.
2. Mode cleaner characterization: Absorption, heating and scattering.
3. Optimize the thermal compensation of ITMY.
4. Calibrate SPOB 18.
5. Meausre the PRC length
6. Lock the PRMI using the 3f signals.
7. Investigate the REFLAIR45 whitening filter issue.

TMS:

1. Repair and exchange the in-vacuum cable for the beam diverter.

ISCTEY:

1. Complete the feedthrough panels.
2. Install the on table cabling.
3. Prepare for move to the end station.
4. Check out ALS electronics in EY.

SEI/SUS team:

1. CPS master clock and associated noise.
2. Improve performance.

(Alexa, Daniel, Stefan)

The RD rotation was adjusted to 120deg. This was determined such that the sideband signal was seen in only I, with nothing appearing in Q.

Note: the RF9 frequency is set to 9099471Hz  (only 300Hz from the FSR). We still see RF AM.

Bubba reports that the installation arm is now attached at HAM4.  Jeff B is preparing to install SR2.  They hope to have the optic inside HAM4 by lunchtime.

If anyone was looking at data from PRMI overnight, I just realigned the etm, causing it to drop lock. 

The MC2 roll mode notch (FM6 in ISCINF) was left off overnight, resulting in a rung up 28Hz peak in MC_L, which was producing a huge signal in PRCL. Once on the peak slowly disapeard.

PRMI locking is now quite reliable. However we still have relatively big power fluctuations.

I recorded today's settings in a setup script: sballmer/tempfixes/setPRMI
Really, this should be fed to a guardian.

In an effort to help the ISC crew use the seismic platforms I looked at ITMY performance today with the various blends and levels.  That is still ongoing though.  Meanwhile, since Stefan is able to lock his PRMI with the ISIs off, I propose that the ISI position loops do not do enough positioning to matter (HEPI is another story.)  So in an effort to make the ISI turn on more 'one button', with the ISI off I loaded the current positions in to the position loop targets.  With the position loops not doing much then, the Isolation can be turned on with the one button.  That isn't to say the ISI won't drift somewhere again too far, but for the moment at least it is 'one button.'  You can look at the first plot of trends to see what changed.  Most changes are very small but RZ is maybe 2urads.  Maybe significant but again, if the alignment is OK with the position loops off, these should be just fine.

So I brought the ISI up to Hugo's configuration of 6 Dec.  Not that it can't be improved or that there are no problems but at least the BLRMS looks pretty good, I think a lot better than turned off.  This configuration is 250mHz blends on Stage2 with T250 blends on stage1 except X & Y with T100mHz.44NO.  This is with level3 controller.  The script actually engages the boost2 rather than boost3 (heard that before haven't ya) but I really didn't see a difference at higher blends when I switched it to boost3 so I don't think it matters.

Again, we certainly need to improve these ISI performance, another day.

 Spent some time looking at the noise of the CPS on the BSC after rerouting the sync signals

  One figure is a matlab plot of some calibrated signals using a fixed target on which there are some VERY bad BS channels

  the second plot is a dtt screen of all of the BSC CPS channels in counts, (BS-V3 is looking at a fixed target, all other channels are looking at motion) with all of the ISIs OFF.

  there are a number of icky channels

I measured the noise floopr of the HAM-6 CPS. This is in the configuration that seemed best at LLO, a ground from the electronics rack and a local ground.

The gold colored line is twice our noise model which is what we were getting at LLO.  I have been using two different targets which are at +/-4Volts and since the noise goes as the square of the

distance we would expect the noise from the channels using the different targets to be  (1+0.4)^2 and (1 -0.4)^2  (there is a 1mm offest) which is more or less what we are seeing at high frequencies. 

At low frequencies (were we use then in the control) it is clearly steepper then the noise model

 there is also a noise spike at 0.5Hz in H2 and V2, I chased this a bit last night and found

  - It doesn't look like it is coming from the CPS electronics, I turned of the power to the CPS (unplugging the calbe in the electronics room) and it was still there

 - when I shorted out the inputs to the HAM SEI interface on channels #1 and 2 it popped up in channel H3 and V3 

 - as far as I can tell it has always been at exactly 0.5Hz

Stefan, Kiwamu

The PRMI lock is now quite solid. After we engaged a dither alignment system for ITMY, we turned on the ring heater on ITMY with a hope it is going to improve the mode matching.

• We set the modulation frequency back to 9099471 Hz which is the nominal value. This was for making sure that the separation of MICH and PRCL is good in REFLAIR_RF45. Although, we didn't do any quantitative assessment. So we have to revisit this.
• Both stages of BS-ISI and stage2 of ITMY-ISI were turned off because they were found to be too loud at low frequencies around 0.5 Hz and also at around 10 Hz (for some reason). Disabling them made the PRY noise quitter and the length RMS improved by a factor of 2 or 3.
• We successfully locked the PRMI with the sideband resonant with the settings shown in the attached screenshot.
• We found four oscillations very close to each other at around 300 Hz which are believed to be the BS wire violin modes. Two of them were so big and 6 orders of magnitude bigger than the noise floor.
• We put a double notch filter in LSC-MICH and PRCL filter banks. This let the mode ring down slowly.
• Also, at the same time we saw a power drop over a time scale of 2 minutes which seemed to be correlated to with the peak height of the violin modes. This behavior went away after the notch filters were installed.
• The PRMI lock was so stable that it did not spontaneously unlock.
• We set up an audio output path in LSC-DARM and used Chris's cool script, rockifo to listen to the sound of PRCL and MICH.
  • It is available in /ligo/home/christopher.wipf/Public/bin
  • For example, rockifo H1:LSC-DARM_OUT_DQ 16384 100
• We imported LLO's dither alignment stuff, but we realized that it only dithered the common mode of the power recycling cavity while we wanted to stabilize the ITMY angle drift. So we decided not to use it.
• We temporarily disconnected the cable for the ITMY green transmitted power and instead plugged in QMON of POPAIR_B_RF18. We used an SR560, AC coupled at 0.1 Hz with a gain of 5000 to whiten the signal.
• We then used the Y-arm dither alignment system to keep ITMY well aligned. We chose 1.7 and 2.4 Hz for pitch and yaw excitations respectively.
• We could close both pitch and yaw loop, probably with a UGF of 0.1 Hz for both.
• We turned on the ring heater at around 00:08 in local time with 10 W in both upper and bottom heaters of ITMY.

We found that the pitch and yaw outputs for the y-arm initial alignment were flipped. Fixed the model and recompiled.

h1asc.mdl: SVN revision 7011.

Following updates of guardian at LLO from the past few weeks, I started updating some sus guardian

New feature for saving alignment :

It is now possible to save the aligned as well as the misaligned position of the suspensions for every optic. This can be done through the IFO_ALIGN medm screen via the Save Alignment menu (cf IFO_ALIGN.png) or with the pyhton script align_save_burt -a -m living in /opt/rtcds/userapps/release/sus/common/scripts/

For more details see llo alog 10436 and 10466

Restoring the saved alignments :

This is done through Guardian by switching between different states of the suspension. Guardian medm screens can be accessed via the ! G buttons in the IFO_ALIGN medm screen (cf IFO_ALIGN.png).

For now, only PRM PR3 and MC2 are running under the guardian and can be restored this way. For the other suspensions, it will need to be done manually (until a guardian process is created).

When the guardian medm screen is open, it is straightforward to switch between aligned misaligned damped or safe via the "REQUEST" menu (cf GUARD_PRM.png)

IFO_ALIGN.adl was updated from livingston but I had to make some modifications to get the links functioning. The new adl file was commited under the svn

1) As Kiwamu pointed out to me, the arguments under the Save Alignment link were in the wrong order (e.g. "align_save_burt MC1 -m" instead of "align_save_burt  -m MC1"), so I modified it for MC1/MC2/MC3/PRM/PR2/PR3/SRM/SR2/SR3/BS/ETMX/ETMY/ITMX/ITMY/TMSX/TMSY

2) Also, the command to create a guardian medm screen (guardmedm) had the full llo path defined (/ligo/apps/ubuntu12/guardian/bin/guardmedm) which doesn't exist here so I changed it to guardmedm without the path. That should also work at llo.

J. Kissel

Though we're confident that the only way to improve the X-arm Test Mass angular performance is to improve the BSC-ISI performance between 0.3 and 0.7 [Hz], I tried tweaking the Level 2.1 Damping Loop design to see if I could do any better, by increasing the Q of the boost filters on the L and P degrees of freedom. Further, I moved the frequency of the P boost down from 0.56 [Hz] to 0.51 [Hz] to account for the difference between the modelled and measured frequency of this mode. Regrettably, I could not improve the strength (at the resonances) of the boosts much more than 5 to 10 [dB] without destroying the the stability of the L & P loops -- I'd already pushed the phase and gain margins of the *lower* unity gain frequency pretty far. As such, the improvement was only in the sharp frequency regions over which I'd focused the boost, but little-to-no change in the RMS. 

We'll continue to work on improving the performance of the ISIs. 

For posterity, I post all of the design information and performance comparisons. The good news is, that my MIMO model of the QUADs can now accurately predict the optic angular motion -- especially Pitch -- at all frequencies where not limited by its sensor noise. Check out the pg 2 of the third attachment for proof!

Details:
---------
allquads_2014-01-31_AllGoodFibers_P.pdf 
     -- Shows a collection of transfer functions of all monolithic suspensions. It shows that compared against the modeled first, top mass, P2P mode at 0.56 [Hz], all the measurements show that this mode is at 0.51 pm 0.01 [Hz]. This is what motivated me to focus the sharp P boost at a lower frequency.
2014-01-31_H1SUSETMX_M0_DAMP_Filters.pdf
     -- Bode plots comparing the 2013-06-14, Level 2.1 Filters against the new 2014-01-31 Sharp Boost filters. 
dampingfilters_QUAD_2013-06-14_Level2p1_2014-01-30_H1ISIETMX_Seismic_SelectPlots.pdf
     -- Using current seismic data input, this is a few select plots from the loop design script for the 2013-06-14 Level 2.1 filters. As mentioned above, it predicts the measured P motion extremely well below ~1.5 [Hz]. Interestingly, the Y prediction is not perfect, but I suspect that below 0.5 [Hz] the signal is dominated by L and P motion of test mass, confused as Y. Especially because the two extra modes that appear at ... you guessed it 0.44 and 0.56 [Hz].
dampingfilters_QUAD_2014-01-30_Level2p1_RealSeismic_SelectPlots.pdf
     -- Selected performance plots with the new sharper boost. Bare in mind that I've used the *model* for the predicted transfer functions, which don't get the first P mode at the right frequency. That's why things appear like they will be unstable, and all sort of gain peaky near the lower unity gain frequency. 
dampingfilters_comparison_2013-06-14vs2014-01-31.pdf
     -- A comparison between the two designs. 
2014-01-31_H1SUSETMX_Level2p1vsSharpBoost_Performance_ASDs.pdf
     -- A comparison of the optical lever performance between the two configurations. Of course, the spectra were taken at different times of day, so above ~0.6 [Hz] the input motion is a little different, but below 0.6 [Hz] the motion is the *same*,  and one can see the expected change in shape of the hump, but no change in RMS. Oh well.


Design Scripts:
SusSVN/sus/trunk/QUAD/Common/FilterDesign/Scripts/
compare_quad_dampfilter_design_20140131_NormalvsSharp.m
design_damping_QUAD_20130614.m
design_damping_QUAD_20140123.m
plotquaddampingcontroldesign.m

Filters and Model saved to:
SusSVN/sus/trunk/QUAD/Common/FilterDesign/MatFiles/
dampingfilters_QUAD_2013-06-14.mat
dampingfilters_QUAD_2014-01-30.mat
dampingfilters_QUAD_2013-06-14_Level2p1_2014-01-30_H1ISIETMX_Seismic_model.mat
dampingfilters_QUAD_2013-06-14_Level2p1_RealSeismic_model.mat
dampingfilters_QUAD_2014-01-30_Level2p1_RealSeismic_model.mat

Due to the non-zero chance of a second cooling unit failing, we are leaving the doors between the MSR and the hallway open for the weekend. We should keep the control room doors closed to reduce the noise.

I made a calibration of the IM4trans and MC2trans SUM channels into uW.

The conversion from W incident on the PDs to counts registered on IMC-IM4_TRANS_SUM_OUTMON is as follows:

[counts/W] = responsivity [0.16 A/W] x transimpedance gain [1000V/A] x differential to single input gain [2V/V] x whitening gain [36dB=63.1 V/V] x ADC gain [1.6384x10^3 cts/V].

This is actually the same for both MC2trans QPD and IM4trans QPDs: 2.087x10^9 [counts/W]

I used this calibration factor to calculate the power on IM4trans and MC2trans currently:

IM4trans counts ~= 57890 counts, which converts to 1.75mW. Comparing this with the expected power on IM4trans:

8.73W into IMC * 0.85 IO throughput * 2400ppm IM4 transmission * 0.1 transmission of BS between IM4 and IM4trans QPD = 1.78mW

MC2trans counts ~= 2.17x10^4 counts, which converts to 655uW. Comparing this with the expected power on MC2trans:

8.73W into IMC * (IMC gain = IMC Finesse/pi = 166 ) * 5.1x10^-6 MC2 transmission * 0.1 transmission of BS between MC2 and MC2trans QPD = 740uW.

Both these estimates for the power incident on each PD agree pretty well so I'll go ahead and add a new filter called "cts2uW" in the SUM_OUTMON paths to give the outputs in uW incident on the PDs.