Following doors being hung on the HAM4 chamber earlier today Phase 3a DTT TF measurements have been taken this afternoon for SR2 (HSTS) suspension as follows:-  

- SR2 M1-M1 undamped results (2014-07-22_1200_H1SUSSR2_M1_ALL_TFs.pdf)

HAM4 ISI Status: ISI unlocked, no damping or isolation loops running.

SR2 alignment: No offset was applied during this measurement.

SR2 undamped measurements from above have been compared with other H1 HSTS suspensions at the same Phase of testing (allhstss_2014-07-22_Phase3a_H1SR2_UnDamp_ALL_ZOOMED_TFs.pdf). The plot key is as follows:-

Blue Trace = Model (hstsopt_metal)
Orange Trace = H1 SRM M1 (2014_07_21_1400), Phase 3a (in-chamber, doors hung) 
Magenta Trace = H1 SR2 M1 (2014−05−07_1083546862), Phase 3a (in-chamber, no doors)
Cyan Trace = H1 SR2 M1 (2014−07−22_1200), Phase 3a (in-chamber, doors hung)

Summary:

It can be seen that back on May 7th SR2 M1-M1 TFs looked good (magenta trace). However, subsequently, SR2 appears to have developed an issue with the M1 LF BOSEM channel (cyan trace). This was not evident in recent TFs taken during close-out activities since there is a window of opportunity to take P and V DOFs. We next need to further investigate the actuation chain (applying offsets, measuring coil resistances etc.) to determine if the fault resides in-chamber or with the electronics.   

All data, scripts and plots have been committed to the sus svn as of this entry.

After HAM work subsided and we were able to get into the BSC, we worked on the ITMy reaction chain DOF alignment as well as the lower stage OSEM alignment.  More of the same tomorrow.

IAS needed a 0.2 mm shift to the North (+X) to bring the SUS into spec position.  I closed the RZ loop at the past (last few weeks while position loops were NOT closed) location(-16200nrad); then I drove the X degree 200000nm from its free hang position.  Jason was unable to see this change and it turns out that this amount of shift is barely out of the instrument resolution.  I drove it another 100um and the shift now is revealed.  The free hang position of the HEPI X Dof was -8000 so I've rounded the Bias Target to 300000.  I believe this position will satisfy IAS.

The Ry Dof was unstable so that will have to be worked out before HEPI can be unleashed completely.

LVEA laser safe

08:35 Scott from Apollo sheet metal on site
08:38 Several surf students going to End-X for PEM testing
08:52 Darkham & Forrest – Going to End-X
08:52 Matt, Kate, Apollo – Working on SR2 and reinstalling door on HAM4
09:22 – Richard – In LVEA for survey
09:25 Travis – Pulling PCal target at End-X
09:25 Nathan – Working in the Optics lab
09:57 Scott from Apollo sheet metal on site
10:00 Arron – Working on Illuminator switch and noise eaters at End-Y
10:00 Cyrus – Fixed JRE error on control room video monitor terminal
10:20 Apollo – Pulling HAM5 south door    
10:30 Matt, Jeremy, Stuart – Going into HAM5 to check for rubbing on SR3
10:41 Karen – Going to End-Y 
10:55 Dave & Jim – Working on hardware watchdogs software at End-Y
11:05 Mike V. – Going to End-X
11:30 Apollo - HAM5 Door replaced
11:42 Paradise Water on site for delivery
13:30 Matt & Jeremy – First contact work in BSC3
13:30 Betsy & Travis – Installing BS baffle in BSC2 and working on BSC1 alignment
13:58 Jim – Balance work in BSC2
14:03 Gerardo – Going to End-X to work on PCal viewport
14:05 Doug & Jason – Alignment work on ITMY
14:15 Jeff – Tilt meter investigation at End-X
15:05 Dave – Restart PEM models to pick up name changes and then will restart the DAC
15:19 Hugh – In LVEA to work on ITMY alignment

I went into BSC2 this afternoon and unlocked and rebalanced the ISI. I started by removing 2 kg of optical table mass in a pattern roughly evenly distributed around the SUS. I then unlocked St2 and looked at CPS's, but the level was still slightly out of spec. I then removed some side wall mass from St2 (a D071200 t1), which brought St2 into spec. I then unlocked St1, took another look at cps's, found everything happy enough, so I packed up. I left the ISI unlocked as I'm hoping to run tf's soon.

Robert, Christina and Dave.

Some PEM names were changed in the CS and EX models. The CS changes are to standarize channels with FLOOR in their names (e.g. FLOOR_XCRYO becomes LVEAFLOOR_XCRYO). The EX change was to fix an incorrect name  (ACC_OPLEV_ETMX_X becomes ACC_OPLEV_ETMX_Y).

the h1pemcs and h1pemex models were restarted, followed by a DAQ restart.

The DAQ restart cleared the 0x2000 errors on the ODC EX and EY models.

Jim and Dave.

After seeing some confusing trend data about what the default RMS-trip level and time-to-kill times are (should be 110mV and 20mins respectively), we went to EY and performed the following tests:

pre-test: put SUS, ISI and HEPI into safe states, no DAC drives anywhere. The IOP SWWDs for SUS and SEI were panic'ed.

1. powered down the HWWD, verified 3 ISI Coil drivers were powered down.

2. powerd up the HWWD, noted it would not boot until we pressed the front panel reset button.

3. read the HWWD settings via BIO connection to h1susetmy model's hwwd part, settings of 110mV and 20min confirmed

4. restarted the h1susetmy model, noted that the hwwd part in the model seems to program the HWWD without being asked to

5. unplugged the control BIO cable from the back of the HWWD (retaining the monitor BIO cable), restarted the h1susetmy model. Its hwwd programming part froze with lack of acknowledgements, but the LED monitoring continued to work

Lastly we plugged everything back in, un-panic'ed the IOP SWWDs, damped/aligned SUS, damped/isolated SEI.

Manual DTT transfer functions are now running on SR2 and SR3 for the next few hours.

(Apollo, Kate G, Jeremy B, Stuart A, Matt H)

Quick alog. More detail to come later....or from someone else

We pulled the First contact on SR2. Optic suface still looks the same as last night in terms of not being great in terms of cleanliness (even tried blowing with top gun for 2-3 minutes after FC pulled). The decision was to go ahead and put in bug report about optic.

Particle counts were great throughout, and after unlcoking Stuart did some quick TFs and gave the all clear. ISI south side unlocked and door went on. Process went really quick and well.

For HAM5 Stuart had seen the most subtle suppression of the first peak of the vertical TF, so must have the ever so slightest of rubbing somewhere ( I am sure he has made an alog about this, I am too tired to search for it). Decision was made to see if could find it. So we pulled door back just enough to allow Jeremy and I to get access to the table (everything still inside the cleanroom).We put flange protection on the bottom section of the chamber just in case (better safe than sorry). Locked half the ISI, adjusted M3 OSEMs as requested and looked for rubbing. Couldnt see anything obvious. Ones I was most suspicious about was the top EQ stops of the intermediate mass on the HR side. Blade EQ stops look fine. Ive backed a few things off. Stuart ran quick TFs nd nothing definitive could be seen from the resolution. Ran a couple average higher resolution TF in vertical. Stuart seemed to be happy with what he could tell in the circumstances so door went back on. Time of door off to door on was around 50 mins (TFs took a chunk of time). We did particle counts throughout and all were low...it really seems that having people not moving about in the BSC chambers correlates with low counts in the HAMs even all the way up at HAM5). Stuart has recordings and hopefully will post.

Note: I also noticed that the nuts on the top EQ stops on the upper mass (the ones in the tablecloth) had not been engaged. With the table half unlocked like it was I wasnt able to get to them in a way to engage them, but the stops appear to be a long long way back from the upper mass, so the chances of them vibrating down to start touching I think it low....well for the two that I could see...cant see the ones on the inside of the table)

South door back on with 4 bolts and my fingers crossed that its all good.

Matt and crew are working at HAM4 to remove second application of First Contact. If the optic is cleaner than yesterday the south door will be put on.

There is slight vertical rubbing on SR3. The south door will need to come off for this to be checked. When the door is off the M3 AOSEMs will also be adjusted.

Betsy & Travis working on OSEM alignment, optic alignment, and ACB install in BSC1.

Travis to remove target at End-X for PCal. The PCal group will be doing reflectivity testing at End-X.

Richard working at End-Y on cabling. 

(Sheila Daniel)

Finshed the installation and alignment of the ALS WFS auto-centering for EY. All 4 dofs were engaged. TFs TBD. The first channel of the MCL controller for WFS A seems to have a bipolar input range, whereas all others are unipolar. This is reflected in the applied output offsets of the servo.

no restarts reported

(lots and lots of people)....and I want to thank ALL these people for all their help today. Everybody was willing to pitch in and help, and was fantastic that that happened.

Its been another long day and I am tired so this will be quick (more detailed report to come)....also apoogies if this alog makes no sense. My mind is mush now.

HAM5 was closed up today. ISI balance was rechecked and slightly altered, clean of chamber  happened, had also to pause for some time where we had to wait until particle counts dropped to level happy to peel FC off SR3 but eventually got both doors on. We did notice that when FC pulled immediately it looked awesome, and then in the time before door went on, started to see small amounts of particulate already coming back. After doing some quick TFs in a couple DOF's it was given the okay to put doors on and they were put on as quickly as we could. We did learn various things on how to speed up, etc.

Rough timeline: 1st contant removed 11.20am 1" optic. 11.44am first contact removed from SR3 optic. North door on ~12.37pm, South door on ~13.14pm.

Changed up the order for HAM4 door and ISI was half unlocked and North door went on before started anything (discovered after door went on that first contact is still on the inside of the viewports :-(...after discussion with Mike L we will pull off the viewports at a later date to remove). From that we had to wait an awful long time trying to wait for particle counts to drop out of the hundreds. Things learned is we found counts spike when door gets put on, couldnt have the BSC chamber cross flow on as would make counts in the hundreds in HAM4, same with people trying to work in BC1, or even lifting a cover elsewhere. Eventually counts went down and we pulled FC on SR2. Unfortunately right at the end of the pull the gas bottle ran dry on the top gun :-( :-(. And immediately looking at the SR2 optic it looked bad...as if we had never used FC. After a bit of back and forth and a round table discussion it was decided we would try to first contact again with everything its its present state. That is to try to re-spray FC using the hold on cone and if that didnt work to paint on FC after first trying blow off anything that we could. We found the cone didnt work (wouldnt fit) and so we painted. Was a pain as coulndt really see it, but we got it done in the end (well done Kate and Rich for staying behind with me to get this done..your help is appreciated more than can express). So will try to pull FC again in the morning and we will see what we see.

Hopefully others will make alogs regarding particle counts, etc. ...and I may try to write a more detaield report at a later date with some photos etc depending on if they turned out when look at.

Stuart A. Jeff K. Arnaud P.

Today, after HAM5 chamber closeout, we took tfs measurements on all degrees of freedom of SR3 and SRM, using dtt. The suspensions were NOT damped during the measurement. SRM looks healthy (cf first pdf, compared with last tf taken in may), but unfortunately we think SR3 is rubbing, looking at the V2V transfer function (3rd page of 2nd attachment, black curve). The first vertical mode at 1.07Hz is unexpectedly damped, and does not look similar as the previous tf taken on July 15th, after the magnet repair. We tried to run the same vertical tf applying offsets in different directions hoping to find a configuration were the resonance would come back to a high Q, but without any luck (cf screenshot). We will run long tfs overnight using matlab to make sure it's not some kind of measurement artefact (which we doubt), and see how it looks tomorrow.

We also noted SR3 M3 osem alignment UL is not ideal (cf 2nd screenshot), which might have been exacerbated by this morning's HAM5 ISI rebalancing. 

Measurements were added to the sus svn :

-----------SRM-----------

Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_L_0p01to50Hz.xml
Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml
Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_R_0p01to50Hz.xml
Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_T_0p01to50Hz.xml
Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_V_0p01to50Hz.xml
Data/2014_07_21_1400_H1SUSSRM_M1_WhiteNoise_Y_0p01to50Hz.xml

----------SR3------------

Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_L_0p1to50Hz.xml
Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_P_0p1to50Hz.xml
Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_R_0p1to50Hz.xml
Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_T_0p1to50Hz.xml
Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_V_0p1to50Hz.xml
Data/2014_07_21_1400_H1SUSSR3_WhiteNoise_Y_0p1to50Hz.xml

Summary of the problem:

We have been struggling for several months with what we believe are direct (magnetic) couplings between the BSC-ISI actuators and seismometers . We have tried to measure and subtract the main coupling (Z to RZ). We have obtained substantial improvement in the T240 response, but no improvement in the optics low frequency motion as seen by the optical levers. Our conclusion at his point are, that we need to identify and subtract the couplings in other directions and/or there is noise injection somewhere between Stage 1 and the bottom mass of the quad.

Low frequency couplings analysis:

The two BSC-ISI units locked at LHO (ITMX, ITMY) give us a great opportunity to study the low frequency direct coupling from the actuators to the sensors. This document compares transfer functions of the BSC-ISI when the two stages are floating (unlocked/free) and  when the two stages are locked. We use two series of measurements performed on ITMY. The goal is to figure out whether the low frequency features in the inertial sensors response are due to motion (translation or tilt coupling) or due to direct pickup (magnetic fields).

Comments are embedded in the document.

The last slide carries the most important information.