Tested photodiodes in ITMX. Testing was done on feedthru E4-6-1, air side. PD forward voltage: Pin1&2: 0.409V Pin4&5: 0.422V Pin7&8: 0.423V Pin10&11: 0.423V Filiberto Clara
Crane work at End Y – Apollo Soft Cycle GV17 at End Y – Kyle ZV-800 viewport installation (HAM3) – Apollo Iluminator and camera installation (HAM3) – Jeff L./Travis Running TF on ITMx - Betsy Running TF on MC1/MC2/MC3/PRM – Betsy GV-8 soft close - Kyle Cryo Pump reinstall on X arm in LVEA – Apollo HAM3 ISI rebalance – Jim/Greg
Replaced Top Coil Drivers in SUS-C7 (U37, and U36) with OMC Coil Drivers. Wire Diagram D1002740 calls out for top coil drivers. New units were placed as follows in SUS-C7 Rack: OMC Coil Driver D1100304 - S1102659 was placed in U37 OMC Coil Driver D1100304 - S1102660 was placed in U36 Filiberto Clara
I'm finishing up my last set on PRM (HAM2). Jim is going in to start work on rebalancing the HAM3 ISI.
Alexa, Stefan, To verify that the Green QPDs on TMSX all have comparable segment gains, we steered the beam on all 8 segments. The whitening gain was set to 30dB. QPDB: Seg 1 14060 cts Seg 2 14000 cts Seg 3 13900 cts Seg 4 14300 cts QPDA: Seg 1 15900 cts Seg 2 17500 cts Seg 3 17100 cts Seg 4 16200 cts QPD A was somewhat more difficult - depending on the QPD B pointing, the beam can clip before reaching the peak value on QPDA. The gains are withing 10% of each other.
We need a single DOF TF on each of the optics we are cleaning next week in order to run a comparison against "on the fly" after pulling the First Contact. So, I am going to run a few this morning to make new references. I'll take MC1, MC2, MC3, and PRM data.
The ITMx TFs failed last night so we are running them with DTT right now.
TF are done, and look satisfying. Results pending
IAS can break down their equipment
J. Kissel, S. Aston I've installed damping filters using exactly what L1 is using (see LLO aLOG 9724). It may not be the most awesomely tuned filters and gains, but it's good enough for now. L = -6.00 T = -3.00 V = -5.00 R = -0.40 P = -1.50 Y = -3.00 Each DOF should have filter banks FM1(0:30,30), FM5(normX) and FM10(Ellip50) engaged. (Note there are other experimental filters lying around in some FMs of some DOFs. Try not to get confused. When we advance to Level 2 filters, we'll clean these up.)
The second loop power stabilisation photodetector array was installed in HAM2. Unfortunately the beam
used for the alignment of the photodetector, the reflected beam from MC3, had the wrong polarisation. One
consequence of which is that the expected signals levels on the quadrant photodiode were a lot lower. This
will not be the case when the real beam into the interferometer is restored.
The beam into the array was aligned through through the input alignment aperture such that the output
of the eight individual photodiodes was peaked. In the end the output of one of the eight diodes was
somewhat lower than the others. This is not because of a problem with the photodiode but because the
input beam alignment was not optimised. The parameter space of one end of the input beam alignment can
be explored by using the Picomotor driven mirror - the last mirror in the optical path to the photodetector
array.
More details to follow in a later entry.
J. Gleason, P. King, R. McCarthy, O. Puncken, R. Savage
[Jeff B, Andres R, Koji A]
Prior to the OMCS TF measurements...
The OMC was fully cabled up (i.e. OMC DCPDs, QPDs, PZTs, DCPD Preamps, 5 BOSEMS)
The height and balance of the OMC glass breadboard on the OMCS were adjusted.
Then BOSEM positions were adjusted so that the flags are centered in the aperture.
The BOSEM longitudinal positions were adjusted so that the flags blocks half of the light.
We also aligned the reaction chain - it now sits within the pitch tolerance at ~1.1mRad up, but we expect it to point to ~600mRad down after we take the heavy FC sheet off of the CP-AR surface.
Also to note - I closed the Ring Heater around the ITMx.
The IMs and MCs have been burtrestored to the automatically generated snap file from monday 11/11 at 20:00
Attached are 10 min trends of the IMs osem signals in the euler basis (Long/Pitch/Yaw) during alignment on monday, and today after restoring the snapfile.
picture 1 : Monday 11/11 from 19:50 to 20:00 PT
picture 2 : Today 11/14 from 10:20 to 10:30 PT
No major shift is seen when comparing both trends
I've looked at the plots, and there is a huge shift of IM1, and shifts that are large on IM2 and IM4. The fact that I changed IM3 on Monday but it's not showing a change is troublesome.
IM1
Delta 800 pitch
Delta 50 yaw
IM2
Delta 115 pitch
Delta 10 yaw
IM3
Delta 0 pitch
Delta 0 yaw
IM4
Delta 70 pitch
Delta 0 yaw
The good alignment time is 5:09PST 11/11, or 1:09UTC 11/12.
To really be confident about your alignment now vs the alignment on Monday, you'll need to trend the alignment slider values, the alignment drive values, and the OSEM readings for 1:05-1:10UTC 11/12, and use that to compare the current IM positions.
[Cheryl Arnaud]
After talking with Cheryl, I attached, a more accurate comparison between two dates : monday 11/11 from 5pm to 6pm during good alignment and thursday during the night (11/15) from midnight to 1am (quieter environment) after the ISS work of thursday, with the restored alignment from monday.
screenshot 1 : position signals in um/urad in the euler basis monday
screenshot 2 : position signals in um/urad in the euler basis thursday night
screenshot 3 : alignment sliders values monday + volt monitor of 1 osem to prove signal is going through the actuation chain
screenshot 4 : alignment sliders values thursday night + volt monitor of 1 osem to prove signal is going through the actuation chain
We should worry if we were seeing a shif of the order of a mrad, which is far from being the case here.
IM1
delta of 80 (not 800) in pitch
J. Kissel, A. Pele Though Arnaud had posted a few of the pictures from our B&K hammering session of ITMX in BSC3 (see LHO aLOG 8497), I post the rest here because I got more pictures that are not necessarily B&K related. I attach four .pdf albums, captioned below; along with a few of the best publicity photos attached in raw form. 2013-11-13_BSC3Cabling.pdf - Nothing to be alarmed by here, but I noticed that tons of cabling were draped from ST0 of ISI-ITMX to their respective feedthroughs in rather hap-hazard ways, and I was worry about potential shorting of isolation between the suspended payload of HEPI and the Chamber. I mentioned this to Jim, and he quickly assured me that the cables are still in a transient state, and will most certainly be cleaned up before the chamber is closed up. I merely post for posterity, so we (i.e. not just folks in SEI) remember what *not* to do. 2013-11-13_BnKHammering.pdf - Just a few more pictures from the B&K hammering session, indicating where I was hitting and a few action shots. As I said, Arnaud has posted most of these already in LHO aLOG 8497. 2013-11-13_ITMXPublicityPhotos.pdf - It's always good to get some shots that can be later used for posters and talks. Here's a fashion show of H1 SUS ITMX. 2013-11-13_IXArmCavityBaffle.pdf - A couple of things to note here: (1) The first two pages show just how incredibly close the ACB is to the QUAD structure as a result of the move decreed by IAS. In page two I'm trying to hold up a 3/16ths allen key up for perspective, but it didn't work out so well. I would estimate the gap at-closest-approach is no more that 5 [mm]. It just gives me the willies. Especially since I gave the ACB a few milli-Jeffs of calibrated excitation, and it started waggling with reasonably high Q at ~5-10 [Hz]. Is the fundamental resonance of this suspension really that stiff / high-in-frequency? Hurumph. (2) This is the first time I've seen the suspension system up-close and personally, so I wanted to get some good shots of it. Very interesting design... (3) There's still some tooling lying around on the baffle itself. We should make sure to grab these before chamber close-out.
The tooling on the baffle is meant to be there to remind me to tighten a loose cable clamp bolt when I go in there to finish up cable routing and photodiode switch out (we had a bad one). The entire baffle will be swept for tools, loose hardware, and particulate as the last thing we do before signing off the chamber close-out.
Travis is cleaned up the cabling today.
This morning Travis, Jason and I made the ~last pitch alignment of the ETMx. We also pulled the FC from the inside of the 2 East viewports and the ETMx CP-AR. However, when we pulled the FC off of the CP-AR, the thin central portion of the sheet left segments of a ring around the center of the optic. Par for the course. And, of course, I could not get any good pictures of the feature so I'll attach a sketch shortly. I'll get with COC to see what I should do - note, I cannot get the spray cone on to resheet the First COntact and start over, so either we'll need to live with these remnants, or I'll have to get crafty with a smaller cone.
But, back to the alignment - we aligned the ETMx to an offset pitch pointing such that when we pull the First Contact sheet from the HR surface, the optic bounces up to point the nominal pitch. However, this does not help TMS with their alignment now. After consult with IAS/TMS we decided to put the offset pitch onto the bias slider of the ETMx. We have the range according to the uRad-calibrated bias slider, however Jason is going to go map it out and confirm the calibration of the slider with his optical equipment (still set up). This should not take long, and he will leave the offset bias enabled for TMS to start their alignment asap.
Attached is my sketch of the CP-AR FC remnants/wisps left after I pulled the full sheet today.
Note, these features are very small and kinda difficult to see, so they might be survivable...
ETMx pitch after this morning's adjustments:
With reference to this alog 8503 We first note it is not a CP but an ERM AR side (TMS side). As a result of it being a ERM AR side (and location) the small amount of first contact should either be left or removed with acetone if you really want too. Cheers, Calum (with input from GariLynn)
Great! Sorry about the error in the reference to a CP - indeed, it is of course an ERM! Thanks!
Also to note - at the time of this alignment, I closed the Ring Heater around the ETMx.
Data is stored in svn appropriate directories dated 2013-11-15_1104.