(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

Mike V, Rick S, Darkhan T

This afternoon the alignment of the ETMX PCal IR path was finalized.  The upper/inner beam did not require adjustment of the periscope optics. The outer/lower path required realignment of two mirrors.

The alignment of the camera optics was finalized. The paths from both camera viewports were adjusted. The camera and enclosure that were installed in the upper viewport on the West side of the beamtube has been removed for this work, and will be re-installed at its final position in the lower viewport on the east side, next to the OpLev transmitter.

Particle counts were taken before, during, and after the in-chamber work.  After entering the chamber, Rick wiped the floor plates to reduce stirring up dust.  The actual counts will be posted as a comment, but the cleaning reduced the after-chamber-work particle counts from ~2000 cts to ~350cts for 0.3 micron/c.f.. A great improvement.

08:55 Daniel and Sheila working on optics table at end Y ?
09:00 Jodi reports H1 PSL chiller is alarming
09:02 Hugh to HAM 3,4,5 to balance check seismic
09:05 Jeff B. and Andres going to HAM 4 and 5 for contamination control closeout work
09:09 Paul and Jordan to end Y to work on PEM
09:10 Jeremy B. and Matt H. going to HAM 4 and 5 for closeout work
09:12 Jeff B. added 200 mL of water to the H1 PSL chiller
09:12 Nathan starting unattended work in optics lab with laser on
09:16 Mike V. to end X, PCAL work?
09:23 Rick called from end X, looking for Mike V.
09:30 Doug C. to ITMY, spool area to calibrate survey equipment
09:37 Jason heading out for ITMY alignment
09:46 Aaron to end Y to install illuminator chassis in SUS rack
09:52 end X is in laser hazard
09:53 Travis to ITMY to work on reaction chain alignment
11:15 Stewart and Arnaud to HAM 4 and 5 to better communicate with closeout team on transfer functions
12:48 end X is laser safe
12:59 Aaron to end Y with power cord for illuminator chassis, and then to end X to install illuminator chassis there
~13:30 Dale leading tour in control room
14:00 start of putting doors on HAM 4
14:11 Jeff K. to end X to measure cable tray lengths
14:12 Stewart into LVEA to start work on SR2
14:46 Hugh to electronics room to check coil driver chassis
14:56 Mike L. going to HAM 4 to talk to closeout team
15:05 Jeff K. back from end X
16:01 Nathan done unattended work in optics lab
16:30 Fred taking 2 visitors on tour through the LVEA
16:30 standing down on putting door back on HAM 4, reapplying first contact

Mike V, Rick S, Darkhan T

This morning Rick and Mike went into chamber to continue with the alignment of the PCal transmitter and periscope, with Darkhan outside. Alignment now looks good.

This afternoon we will continue with alignment checks of the camera mirrors.

Particle counts were reasonable before work commenced (attached photo IMG_0086), however after exiting chamber counts were very high (attached photo IMG_0087).

This is most likely due to stirring up dust; we will wipe the floors as well as the PCal periscope and Manifold Cryo Baffle which are noticeably dirty.

Some odd noises were also coming from the clean air compressor (very low audible tone), Kyle is investigating.

Based on yesterdays FC troubles I went back and had a look at some of my alogs regarding humidity in chamber.

By looking at the various pics I posted of particle counts in links:

https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12874

https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12873

https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12866

https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12859

You can see the humidity in chambers varies from 13%-33%. I was surprised at this, and I have to take back what I had said to Kate and Calum yesterday at how I said I had noticed that the humidity levels usually stayed pretty constant in chamber here at LHO

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.