Jennie W, Madi S, Sheila  D,

Summary: JAC REFL A PD and WFS A and B are well-aligned and the beam is centred on the steering mirrors, but still some sign confusion on the readout for the WFS A quadrants and the WFS B DC readout (the QPD).

Earlier Madi and I went and re-centred the beam on the IOT1 steering mirrors JACR-BS3, BS4, M8, M9, M10. We then re-aligned the REFL PD and both WFS QPDs.

While centering we realised the degrees of freedom were switched.

After checking in the QPD input matrix for both WFS A and B, I found these were the wrong sign.

These matrix parts were copied from the IMC model and I didn't realise the IMC QPDs have a switch between pitch and yaw due to the periscopes that carry IMC REFL beam from MC1 to the in-air IOT2L.

I have switched both JAC QPD input matrixes to the values shown here.

I also checked the WFS I input matrix vales for A and B and these appear the have the correct signs for each quadrant.

Then I went to the table to do some sign checks on the QPD RF readouts to confirm these are hooked up correctly.

First I locked the JAC and then detuned it so the WFS signals are dominated by length noise. An offset of 0.4 in JAC-L_SERVO_OFFSET can be used to detune the cavity without unlocking.

Then I checked that the motion of the across the QPDs matches what we measure.

Moving anti-clockwise on pitch adustment knob for WFS A is down on QPD and on JAC-WFS_A_DC_PIT.

Moving left on QPD is down on  JAC-WFS_A_DC_YAW.

QPD A seems to have the correct matrix.

As I was doing these adjustments I looked at the four demodulated I-quadrature signals for WFS A.

Whent the beam moves down in pitch quadrant 2 and 4 go down and quadrant 1 and 3 go up - this is confusing as 1 and 3 should be diagonal from each other. See ndscope.

When the beam goes down in yaw quadrant 1 and 4 go up and quadrant 2 and 3 go down - the opposite way to what we expect from the motion on the QPD. See ndscope.

I did the same series of checks for WFS B

Moving anti-clockwise with the pico mirror pitch adjustment knob is up on the QPD itself but down on the WFS-B_DC_PIT channel, this is wrong.

Moving anti-clockwise with the pico mirror yaw adjustment knob moves right on the QPD itself and up on WFS_B_DC_YAW channel - this makes sense.

So maybe we need to change the input matrix for this or fix some wiring.

Still need to check the four demodulated I-quadrature signals for WFS B.

NB: Two months ago we started commissioning the JAC WFS and discovered that the X and Y on the A picomotor are swapped somewhere in the chain, see alog #89437. This probably needs the control wires swapped at the pico signal distribution box on the table itself but the picos are not hooked up at the moment as the controlled is shared with IOT2L which is unplugged for vent work in HAM2.

PSL power into JAC 200mW. Jennie was able to lock JAC without much problem.

Jenne put MC2 back to march 2026 (in-lock) alignment in PIT and YAW using osem (not the slider) taking into account ISI (HAM3) Rz. 

To see the fringes, we injected 600 counts 0.2Hz into H1:SUS-MC2_M1_DRIVEALIGN_L2L_EXC. IMC flashed right away but the transmisison fringe looked like a weak horizontal line. Moving MC2 alone did not make the fringe converge.

Jenne moved MC3 and MC2 (and MC3). Improved some but not drastic. Tried JM3, again improved, but not drastic. Jenne was able to see the MC2 TRANS SUM but it was awkward and slow. At this point, at least the beam was not a straight horizontal line any more, we saw HOMs both in PIT and YAW, sometimes even 10 and 01 and what might have been a dim 00 spot. According to Jenne, the maximum MC2_TRANS number observed (about 3 after subtracting DC offset with 200mW input) is about 10% of what we expect with a good alignment (300 counts with nominal 2W).

We need a better alignment to be able to see the beam in the ISS path, though, I couldn't see anything.

I wanted to see the PRM reflection on the ISCT1 REFL camera as it will make the alignment easier (because we can see the IMC transmission beam shape).

Inside ISCT1, the beam was making it to the BS for the 1F diode but was hitting the mirror holder of the mirror for the BBPD. I touched up the common steering mirror for 1F and BB (just downstream of the shutter) so the beam goes to the direction of BBPD (and of course 1F PD) but could not see the transmission of the mirror for the BBPD using a card and a viewer, probably because the power was too small. (We're injecting 200mW, MC2 transmission is a small fraction of that as of now, and the REFL path is supposed to handle 60W.) No beam was seen on the camera either.

On Monday we might temporarilly move the BS for the BBPD out of the way so we can see the beam on the camera.

I had a look at some of the data from Leo Schrader's SURF project, in particular the measured overlaps of the sqz beam with the OMC posted 86485 and the measured q parameters on SQZT7 posted in 86365.  

I first took the measured q parameters, and using finesse propagated them to the OMC and calculated overlaps, which are plotted as sqrt(vertical overlap * horizontal overlap).  The attached scatter plot shows the predicted overlaps compared to the measured overlaps as the ZM4 + ZM5 strain guage voltages vary.  You can see that for the nominal O4 settings of -0.4V ZM5, 6.2V ZM4, the measured q agrees pretty well with the measured overlap.  Moving away from the nominal values, some of the measured qs do not seem very compatible with nearby measured overlaps.  (note, these measurements cover the whole PZT range of 0-200V for both psams, the strain gauges just have different ranges.)

I then tried to use the overlap data to take a gues at what this means for the actuation range of ZM4 + ZM5 psams.  I used the following information from Camille to estimate the ROC of ZM4 and ZM5.  

• ZM4 is SN1, characterization data in E2100289 indicates that before the preloading was changed in chamber, with 0V on the PZT the optical power was -106mD.  In 75677 the pre-load was increased by 29 in lbs, T2300426 says the preload should increase the optical power by 2.4 mD/ in lb of preloading, so after preloading the optical power with 0 V on the PZT should have been -36mD, or an ROC of -55.5 meters.  0V on the PZT now corresponds to 2V on the strain guage.  
• ZM5 is SN4, E2100291 says with 0V on the PZT the optical power was 667mD with 20 in lbs of preload.  75709 says the preload was increased to 47 in lbs, so 27 in lbs of preload was added.  I assumed that the optical power change with pre-load is the same for ZM4 as ZM5, and estimate that the optical power after the pre-load change the optical power with 0V on the PZT should be 729 mD, or an ROC of 2.737 meters.  0V on the PZT now corresponds to -5.2V.  

I used these estimates for optical power with 0V on the PZT and varied a linear slope of optical power per strain guage voltage.  Assuming a slope of mD/V for each psams, I estimated the ROCs of each mirror.  For any set of psams slopes, I estimated the q before ZM4 by using the measured q for the nominal strain guage values of 6.2 and -0.4V. I flipped the sign of the real part and propagated it back to before reflection off ZM4 using the estimated ROCs for that slope, then flipped the sign of the real part again to reverse propagation direction. (Thanks Keita and Disha for help understanding how to flip the qs).  I then propagated that estimated q back through the ZMs allowing the strain gauge voltage to vary and calculated overlap with the OMC.  This approach garantees that the nominal strain gage of 6.2V -0.4V the contour will match the 2.3% mismatch estimated from the measured q there. It would be nice to do an actual fit, and also allow the ROCs at 0V on the PZTs to vary, to see if we can get a better match to the dataset that way.  

In the example contour plot I've put ZM4 at -10mD/V strain gage, which means -0.36mD/V PZT, and the O4 nominal ROC would be -25.6meters.  ZM5 is at -13mD/V strain gage, which means -.47 mD/V pzt and nominal ROC of 2.99 during O4.  

Lastly, I made a plot of propagation of the measured qs to the output of the AR side of SRM, that we can compare to Evan Hall's much nicer plots of SEC and arm cavity modes at SRM.  

The script used to make these plots can be found in the commissoning-modeling-repo here.

TITLE: 05/08 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

MC2 was fixed (cabling issue---see their alog).  ISS team went out to HAM2 late this afternoon.
LOG:

• 1513-1542 LVEA garb checks (kim.dawn)
• 1528-1536 MC2 work fixes continue w/ work at racks (Rahul)  
• 1549-1558 restoring mc2/pr2 cables (rahul)
• 1622-1628 reboot coil driver for mc2  (rahul.marc)
• 1655-1704 Dust monitor being power cycled, since it's been down (ryanC)
• 1645-1800 LVEA technical cleaning (kim)
• 1700-1830 Back to HAM3 for more checks (rahul.marc)
• 1703-1818 open light pipe, working on iot1, no locking for jac (jennie, madi)
• 1711-1945 BS/BBSS OSEM swaps (thomas.oli)
• 1745-2001 SQZT7 back panel off for table work (sheila)
• 1834-1852 Back to HAM3 area for another round of checks (rahul.marc)
• 1851-2000 Continuing JAC work at IOT7 & closed light pipe when out(madi.jennie)
• 1900-1947 EX grounding studies (robert)
• 2016-2110 Going into HAM3 for cable checks (rahul.marc)
• 2036-2300 FARO-ing ITMy @BSC1 (jasaon.ryanC.)
  • 2054-2300 Stephen joining
• 2110 Fixed MC2!  Mix up in the cable due to install and/or drawing (rahul, marc)
• 2125-2150 Woodland High School (Maggie)
• 2110 Continue ISS Array work at HAM2 (kieta,elenna,jennie)
  • 2255 elenna out
  • 2300 jennie out
  • 2305 jenne in
• 2110-2300 Checking IOT1 JAC stuff (jennie)
  • 2311 back out
• 2234-2305 PCal checks at EX (marc)
  • 2250 Marc plugged in cables and we have data for channels he was looking at
• 2239 EX grounding checks (robert)
• 2245 Checking on ISS work (rahul)
• 2315-2323 TCS chiller famis check (corey)
• 2327 Grabbing headsets for ISS array group (oli)

Addressed TCS Chillers (Fri [May8] 413-423pm local time) & CLOSED FAMIS #28640. 

For measurements below, measuring from "top" of the red floaty ball.

• TCSx Chiller:  Had level of 29.7 cm.  Added 50mL for 30.5cm.
• TCSy Chiller:  Had level of 10.8 cm.  Added 0mL for 10.8cm.  
• There was no water in the small cup under the slow leak.

Marc, Oli, Jeff, Jenne, Richard, Betsy, Fil, Keita, Rahul

Yesterday afternoon, Jenne pointed it to us that she was struggling to point (move in pitch or yaw) MC2 suspension in HAM3 chamber - she was applying bias on Pitch dof and was not seeing optic move accordingly (this was to get the beam in HAM2 for ISS PD work). We then started troubleshooting  MC2. We started with the usual health checks (trying to damp the sus, TF measurements, M1 osem spectra) and it clearly looked that something was off - though we were not able to pin point on anything. Fil and I then swapped the cable 01 with cable 02 (basically trying to run MC2 using PR2 electronic chain for T1, T2, T2 and LF bosem - for ref. see wiring diagram D2300383, page 01 for MC2). When we (Oli and I) tried controlling MC2 using this, the results were all the more confusing.

This morning I restored the MC2 and PR2 cables back to its nominal state. Marc and I then started looking into the electronics chain of MC2 - poking each stage one by one. We started at Satamps (in the LVEA near HAM3 chamber) where I applied some offset at the CD on the medm screen and Marc measured the output voltage. For bosems T1, T2, T3, LF we measured 230mV and for RT and SD (these two bosems on MC2 share the electronics chain with PR2) we measured 350mV. We then moved to CER and repeated the same measurement at the MC2 coil driver and the result was no different. To check the DAC card and AI chassis we routed MC2 through another Coil driver (used by PR2) and yet there was no change in the output voltage. We swapped out the satamps and coil drivers to look for any change - found none. This meant that the electronics chain for MC2 was  healthy, hence we restored everything.

Richard then suggested to measure the resistance of the coils on the BOSEMs at the satamps. For T1, T2, T3 and LF it was found to be around 16 ohms (much lower than what we expect) and for RT and SD 40ohms (which is the correct value). Around lunch time Marc and I talked to Jeff kissel and everything at this point was pointing towards the suspension (either the bosems or their connection at the new feed through) in Ham3 chamber. After lunch time Marc and I headed to HAM3 chamber. After looking at the dust count (measured in lower 10s), I opened the curtains on the +Y side near MC2. I then identified the M1, M2 and M3 stage cable on MC2 and followed it to the connector on the ISI table. I then followed the table cable to the feedthrough connection (in vacuum side). Marc was standing outside the chamber near the feedthrough side (in air). I then started unplugging the cables on each stage one by one and initially it was very confusing but very quickly we realized (to cut the long story short) that - the M1 and M2 stage cables were not correctly connected at the feedthrough (in vacuum side - see D1002874). To confirm this we measured the resistance of the bosem coils at the D6 feedthrough in HAM3 chamber. The top F1 and Bottom F3 connection were showing out 16 ohms and the middle F2 was showing 40ohms. This told us that the middle F2 connection belongs to the M1 stage and the top F2 belongs to M2 stage - see below for clarity.

Given below the flange layout in HAM3 chamber (D1002874)- D6 F1 and F2 were incorrectly connected. Marc and I changed that on in-air side.
Old connection - D6-F1 F DB25 SUS MC2 M1 T1T2T3LF OSEMs. New connection D6-F1 F DB25 SUS MC2 M2 OSEMs
Old connection - D6-F2 F DB25 SUS MC2 M2 OSEMs. New connection D6-F2 F DB25 SUS MC2 M1 T1T2T3LF OSEMs
Did not touch - D6-F3 F DB25 SUS MC2 M3 OSEMs

 Oli took transfer function measurements and will post the results below. In the meanwhile we can say that MC2 is healthy and back in action.

Ryan Short, Tony Sanchez, Sheila

We took beam profiles of the sqz beam in the homodyne path using the Thorlabs M2Ms beamprofiler extension.  It made collecting data for a variety of psams settings much faster than using a scanning slit profiler alone.  

Tips for using this very nice extender kit:

• The visible alignment laser made alignment easy.
• We used the lens LA1461-C for 1064nm, the list of lenses and wavelengths is here: lens list
• make sure that the unit is plugged in, powered on with the power button, and connected to the laptop before you start the software.  Close and re-open the software if "translation stage control" and "M2 set" don't show up for you at the bottom of the "beam settings" window.  Once they show up you just have to go to the M^2 button and hit play to make a measurement.  
• You can get the fit beam parameters by saving a pdf by clicking the button that says "Save test Protokol", you have to hit save twice on the screen where you type a file name and again on the next screen.  "Save Measurement Data and results" gives you all the data, but not the fit beam parameters.  You again have to hit save twice.  
• Sivananda Reddy contacted Thorlabs and posted a diagram of where the reference plane is in the dcc: T2500077

We spent some time refinding the IR beam on the SQZT7 IR PD, documented this in it's own alog so it's easy to search: 90183

We set the profiler as shown in the attached photo.   The flipper mirror is 50.75" from the bottom persicope mirror, a steering mirror is 225mm from that, and the reference plane is 260mm from the steering mirror, so the reference plane is 1.774 meters from the bottom periscope mirror.  Leo Schrader has a helpful list of distances in the google document linked to T2500228.

• In 85282 Leo measured the beam distance from the top to bottom periscope mirrors to be 574mm. 
• The distance from the top of the persicope to the beam diverter was measured to be 84.5" in 61755.   
• In 75749 the distance from the beam diverter to ZM5 is listed as 1183.54mm based on a CAD drawing from Don Griffith. 
• This means the total distance from the reference plane to ZM5 is 5.678 meters.  We have left the profiler and temporary mirrors in place so that we can use them during the upcoming HAM7 vent.  

J. Kissel, M. Robinson
ECR: E2600106
Drawing: D2400143-v6
Assembly: D2400107-v5

I'm delighted to share that the new version of the SPI Pathfinder's ISIK Transceiver's custom breadboard (D2400143-v6) has arrived on site today! Big thanks to Greg and Levi at RDL Machine for rushing this thru their shop, and then hand-delivering it to me at a meet-up in Pasco this morning.

Mitch and I did a quick inspection and crude fit-checks of the plate prior to handing off to Chris who's hard at clean-n-bake work in the VPW, and here're some pictures.

The things that were keeping me up at night:
    - Will the new alignment peg system for the IXM mounts work? YES! I used a broken-but-good-enough Newport U100A mirror mount I had on my desk, which is close enough in dimension to the in-vac Siskiyou IXM100 mounts (D2400208 and D2400209), and it seats up against the pegs really well, and the mounting hole lines up. 
    - Will our fingers fit around the knobs given the size of the new slots for the IXMs? YES! There's plenty enough room.

And just to nip the "that looks different, why?" questions in the bud:
    - The Fiber collimator IXM mount positions for R_F1 and M_F1 *don't* have an alignment knob slot. That's intentional, because we still need those "utility" holes behind that mounts as mounting spots for the SLIC Shroud that goes over the SPI transceiver when fully integrated into the detector.
    - There is one slot, for the M_M3 mount that is *not* entirely thru the plate. That's because on the *back* side, that slot would have routed through the shoulder relief around the mounting hole. As such, I tested that we still have finger room with alignment knobs and that also works fine.

Off to clean-n-bake!

Sheila, Ryan Short, Tony

Just adding this screenshot to document that we found the SQZ seed beam on the SQZT7 OPO IR PD with seed dither locked and these slider settings. 

Keita, Elenna, Rahul

Yesterday, when we opened the curtain in HAM2 chamber (for ISS PD installation work), we found a dead fly in the chamber (not sure how long it was dead inside but the body felt very fragile, but fortunately it didn't break apart while it was taken out of the chamber) - please see two pictures attached.

The fly did not wear any laser goggles, nor it had any clean garbs on, but most probably it endured UHV and IR laser during its stay inside the chamber. 

J. Freed

An error was found in the plot of Keyrad4r.png from 88873. The SPI budget was overestimated by a magnitude of 3. It is corrected here. 

The code for this plot is being stored at https://svn.ligo.caltech.edu/svn/seismic/Common/SPI/PhaseNoise/python/

R. Crouch, J. Oberling, B. Weaver, S. Appert

We are done with the surveying of the aLIGO BS on the mechanical test stand.  I'm still working on processing the data but can give a quick overview of where things stand:

• With respect to the ISI, the BS is within the aLIGO install specifications (lateral/vertical +/- 1.0 mm; longitudinal +/- 3.0 mm)
  • Position deviations when looking normal to the AR surface
    • Lateral: -0.7 mm (left)
    • Vertical: -0.8 mm (low)
    • Longitudinal: +1.8 mm (in the +X/+Y direction)
  • Will rotate these to the IFO coordinate system at a later date, once all data has been processed
• BS Pointing is NOT within the aLIGO install specification (Pitch +/- 55 µrad; Yaw +/- 190 µrad)
  • Signs reported using the standard SUS sign convention (positive pitch is down, positive yaw is CCW when looking top-down)
  • Pointing deviations from nominal (Pitch: -446 µrad; Yaw: +0.7849 rad (44.9699°) from the +Y axis)
    • Pitch: -200 µrad
    • Yaw: -710 µrad
  • The yaw deviation appears to have been counteracted by a CCW yaw shift done via HEPI once the BS was installed in WBSC2 back in 2013; no explanation for the pitch deviation, but I do recall that pitch did not hold very well on the journey from the test stand to the chamber back in 2013, so there's no guarantee that our measured pitch here is fully representative of the BS optic pitch from in-chamber
  • We have a suspiscion there is an error in the test stand monument used to do the pointing alignment back in 2013, and potentially an error in the LVEA monument used to the in-chamber pointing alignment; working out a way to test that with the FARO
• The BS SUS cage mostly hangs around the aLIGO position tolerances, but we never measured it during the 2013 install (as our target was to place the optic, and the cage ended up wherever it ended up), so this is the first data we have on its position

I'm working on a larger alog tying together all of our BS and WBSC2 measurements (WBSC2 support tube ends, BS in-chamber, and BS on the test stand) to provide a more complete picture of the BS alignment as we have measured it these last couple of weeks (it's going to be a long one); this alog will have the full set of data from the various test stand measurements.  In addition, the SUS and IAS teams met yesterday to discuss our path forward.  We decided that, despite the error seen in pointing on the test stand, we will align the BBS to its nominal position and pointing w.r.t. the ISI on the test stand.  Once back in-chamber we will use the BBS SUS cage position as the metric for adjusting HEPI to once again place the BBS in its nominal in-chamber position; pointing will be restored with the BS optical lever, as originally planned.  I'll write up a RODA documenting this decision and upload it to the DCC ASAP.

This completes LHO WP 13210.

Edit: Some spelling and grammar clean up.

Ibrahim, Betsy, Rahul

First contact was successfully poured on BBS01 AR side. Pictures below.

Ibrahim, Betsy, Rahul, GariLynn

Following AR side first contact removal, we did our first flashlight inspection of the AR side (S2) of the optic. We found that there were 4 spots of varying size all under 1mm, perfectly circular. They seem to look like water (look at image). We contacting COC (GariLynn), who informed us this may be some coating defect. Nontheless, we tried cleaning it.

There are 2 smaller spots on the side of the optic (see image). There are 2 other spots near the center, with one being pretty dead on-center.

First, we used acetone with a cotton swab to wet two spots (the ones on the side). This didn't work and the spots were still there.

Second, we followed T1800350 to clean two spots with water, then immediately apply first contact. This didn't work either.

We will continue to clean spots with water tomorrow. Images below.

TITLE: 05/06 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
SHIFT SUMMARY: Lots of work being done in the LVEA. Scaffolding was erected around GV7, the BBS is here and getting magnets bonded and cleaned, the IAS team is finishing final shots on the old BS, CP1 is still warm, SPI plate was put onto HAM2, and more!
LOG: 

J. Kissel, J. Warner
ECR: E2400026
WPs: 13237, LHO:13238
Final Design Doc: T2400145
Relevant Systems Level Drawings:
    . Mechanical Assemblies
        :: ISIJ Reflector D2400102
        :: HAM Table Baffles D1700335
        :: HAM2 Systems Layout D0901083 (not yet-inclusive-of-SPI)
    . Electronics Wiring Diagram 
    . Cable Routing In-vac Cable Routing Plan from G2401479 (pages )
    . Flange Layout D1002873-v11

Executive summary:
    - Removed ISIJ +X-side, center, HAM2 ISI table baffle from D1700265-v4 Type 2 
        :: Bracket mounting bolts left screwed into ISI optical table for this will eventually become a D1700265-v4 Type 3 and remounted.
    - Installed ISIJ Reflector + QPD Assembly D2400102 on +X ISI side wall (D071057-v2), with its shroud (D2500030) in place
        :: We didn't weigh it, but the SW Assembly predicts a mass of 1.96 [kg], which we can likely round up to 2.0 [kg] with the shroud installed.
    - Routed and connected QPD read-out cable system to D3 flange, F10 spigot.
    - Routed and connected picomotor cable system to existing D1101515 quadrupus leg Cable #3, J4 
        :: Cable #4, J5 is connected to IO PM5 mirror, Cables #2 J3 and #1 J2 were reset in neat coil with connectors floating to avoid electrical grounding as before.
    - Nudged make-shift baffle system using D1700261 ballast mass baffle mounted vertically on the +X / +Y / Beam Height corner of the chamber wall upon entry into beamtube.
        :: the will DEFINITELY need a technically-minded reset.

In at 10:30a PT and out by 12:30a PT. It's so lovely when everything goes to plan!

Pictures and further info to follow in the comments below.

Pictures and the timelapse video from the BSC2 Cartridge (alog 90021) last week are attached and/or at https://caltech.box.com/s/4ahvfvdnaev8iiz3ktgda8g00srpvv1x

The BSC2 cartridge was removed from the BSC2 chamber today and placed on the Test Stand in the West Bay (+Y bay).  The lift took 3 "test lifts" to make very minor adjustments to the CG prior to lift out of the chamber - on the 4th lift, we were very well balanced so embarked on the flight.
Like LLO, the BS had it's "Stay Leg" assemblies and Vibration Absorber Assemblies removed for the flight.  This means it was probably lighter than the 2013 time (alog 5689) when we did this which had the weight slightly heavier.  The cartridge plus 3-point lift fixture and load cell together all weighed 9380 lbs.  It was rotated 90deg Counterclockwise per the procedures and landed on the threaded rod in the test stand with little issue other than careful craning and spotting.
All went as expected and according to the procedures E1200433-v3, E1200971-v4 and associated docs.

Mitchell, Travis, Tyler, Randy (on crane) all up on the platform
Jim and Tony inside of BSC2
Gerardo, Jordan on the eMod as Support
TJ on the camera
Betsy soaking it all in (support)

A pre-lift meeting was held to go over the teams and maneuver details (again) at 9am prior to work starting.

Particle counts up at the dome level were all 0,0 before starting.
More photos and videos will be posted when those folks have them available.

Covers used - A BS/QUAD SUS tube cover up underneath, an ISI cover up on the ISI, the BSC Cartridge sock which encased the whole thing, dropped down to Jim and Tony once the lift was up a couple feet.  

The bulk of the work was from ~10:30am-1pm.  Most of the time before was getting folks in headsets and gear and getting equipment on.