Installed one watec 902H with a 300x zoom lens on the Y beam manifold looking at the baffle for ITMy.  Installed an illuminator on a BSC8 port in the vertex with remote controllable power supply for access from EY.

Installed a Sony camera on BSC 6 spool looking at the ETM.  And an illuminator on a spool port that is powered from the old DC power rack in the LVEA.  

Ported the video signal from the LVEA to the End station and From the end station to the MSR but have a problem with the MSR as we can not get sync. so lines are rolling through the frames.

Will work on getting video into the control room later.

GregG, MitchR, CoreyG, JimW

Today Stage1 was completed and flown to the test stand where it was connected to Stage0 on our seventh assembly. This means that MOST of the mechanical superstructure on LHO's last HAM ISI is completed. Still a lot to do (spring pull-down, actuator and sensor installs, optical table, etc.) but most of the remaining sub-assemblies are put together and are just waiting to be attached. The finish line has never been closer...

(Betsy, Danny)

The first secondary prism was glued to MC2 yesterday. It witnessed a 12-16 hour room temperature cure followed by 6 hours of heat lamp curing.  The optic was stowed in its cake tin for HVAC work planned in the lab tomorrow.  The second primary and secondary prisms will be glued on to the optic next week.

I applied lots of caution tape to the bottom of the spiral staircase to prevent folks from accessing the stairs, E-module, or work platforms around the chamber. I will apply appropriate signage tomorrow.

I spent some time today clearing paraphernalia from ISCT10 and then consulted with Keita as to disposition of said items. Keita will follow-up on getting items put away appropriately. He also asked for the table to be craned into the Squeezer Enclosure so Bubba and crew will take care of that tomorrow.

First thing this morning, the doors were returned to HAM6 and the south door was removed from HAM5. Brushing was completed in HAM5 before lunch.(The condition of this chamber is much better than what we saw in HAM6 and cleaned up nicely.) After lunch, the crew did first vacuum, unwrapped the support tubes, vacuumed the bellows, and started wipe down. By the end of the day, about 1/2 the chamber had been wiped down: that is much closer to the rate of progress that we are used to instead of the VERY SLOW pace we saw in HAM6. We hope to close out tomorrow.

 

Kyle- 
Soft-closed GV6, roughed-out GV1 annulus, valved-out BSC8 annulus aux. pump cart, opened GV5, GV6 and GV17

One of the GS13s of HAM-ISI unit #6 (Pod #94) appeared to be defective this week (see aLog 3183).

Greg and I opened it this morning. Two flexures were broken.

• D0901318-v3, s/n 124 (Pic. 1)
• D0901319-v4, s/n 199 (Pic. 2)

One can see wear on the non-broken side of D0901319-v4, s/n199  (Pic. 3,4). The pattern is very similar to what Jim reported in the SEI Log a few months ago.

We also found a small flexure debris. This debris was identified as being part of D0901318-v3 s/n 124 (see black line on pic. 5).

The pod was tested at reception on a leveled surface. Nothing abnormal could be seen on its response at that time. It was then installed in the ISI. No major event was reported (drop/shock/…). Spectra were taken with the ISI tilted and the pod appeared defective. Any spectra, even with the ISI leveled showed it defective after that.

As it already happened, it is possible that the shocks, endured by the instrument during its shipment, damaged the flexures. In these conditions, tilting the pod back and forth to install it, and/or tilting the ISI for testing purposes, could have lead to the breakage.

We have shockwatch data for this shipment. Greg will post it later on.

[Thomas, Aidan]

Thomas and I tracked the source of clipping on the Hartmann sensor beam. The return beam from the ETM was hitting the edge of one of the mirrors in the back corner of the ALS table (see attached diagram). We tweaked the alignment so that the beam was centered on that optic.

The new beam profile on the HWS is attached. There is no sign of clipping now, but the beam quality is a poor Gaussian. There also appears to be horizontal fringes on the beam.

Max F., Keita K., Daniel S.

We had a hard time finding the beat node by adjusting the crystal temperature. Once we came close to the correct frequency the line would simply vanish. This seems to be related to mode hopping. The diode current was about 1.43A. We noticed that increasing the diode current by simultaneously adjusting the temperature to keep the beat frequency close to 40MHz allowed us to widen the acceptable temperature range and improved the beat node strength. Around 1.9A there was another mode hope, so we backed off the diode current to 1.666A. This re-adjustment of the diode current seemed to have increased the gain in the PLL. We had to reduce the common gain to -23dB (down by 3dB) to make it stable again.

We also found that the gain in the digital temperature stabilization servo only has a small range where it would work. Adding 10dB would make it unstable, whereas subtracting 10dB made it go to the rails. Even with the correct gain, we noticed that the PZT voltage would often go beyond +/-1V. Our readback has a gain of 10 and saturates just above 1V. (This readback is used as the error point of the temperature stabilization servo.) The following changes were made to the ASL common mode board, S/N S1102638 (H2 EY): 
R272 removed (from 374), 
R271 replaced by 0 Ohm (from 3.32K). 
The readback now has a gain of 1 and the temperature servo should work over the full PZT range.

The H2 SUS ETMY Simulink model was modified to incorporate the Optical Lever photodiode signals on the second ADC card of 'h2susb6'.  The EPICS library part was removed from 'h2susetmy.mdl' which imported the signals from the temporary H2 ETMY optical lever Simulink model.  The signals are read from the second ADC, ADC_1, on the H2 SUS ETMY front-end,'h2susb6'. After a few recompiles, the model was installed, along with the 'h2sustmsy' model.

(corey, eric, hugo, jim)  [this is an entry for work on Tuesday]

#6

Installing more walls, several iterations of balancing system, measuring Lock/Unlock values.

And yet more serial number info for cables

Corner1

• Actuator H:  S1106673
• Actuator V:  S1104096
• GS13:  S1106665
• L4C:  S1106653

Corner2

• Actuator H:  S1104097
• Actuator V:  S1106676
• GS13:  S1106670
• L4C:  S1104709

Corner3

• Actuator H:  S1104099
• Actuator V:  S1104101
• GS13:  S1104701
• L4C:  S1104602

#7

Started staging for Pitchfork/Boxwork assembly.

Helicoiled Outer Walls

(corey, greg, hugo, jim, mitch)

#6

Performed ISI tilt measurements.  While doing this it was discovered that H1 (s/n094) was not acceptable.  It was removed and was replaced with the one spare horizontal GS13 on hand (s/n 018).  Then continued with performance measurements on the ISI with new H1 GS13.

#7

Ribs were prepped for Stage1 Assembly.  These Ribs were individually installed on the Stage1 Floor (vs. pre-assembling the Pitchfork/Boxworks and installing them on Stage1).  Keel Walls were installed, and other parts were also set up on Stage1.  Should have Stage1 on Stage0 tomorrow.

Attached are plots of dust counts > .5 microns.

Burped GV5 gate annulus into aux. pump cart and switched from Turbo to Ion pump pumping on the YBM -> Didn't valve YBM into CP1 yet as viewport work is still taking place on the YBM (op levs, camera).  

The support table was removed from HAM5 first thing this morning then the condition of the chamber was documented. The support tubes were wrapped and brushing was started. The crew got about a quarter of the chamber brushed before the end of the day.

Part of the Assembly Validation testing of HAM-ISIs (that happens in the staging building) consists in taking power spectra with the ISI tilted. It allows us to check that the sensors, especially the seismometers, work in tilted position as well. To do so, spectra are taken with a 10kg mass set at each of the 6 corners of the optical table (Locations A to F in ISI_Tilted) 

This test revealed that GS13-H1 (Pod #94) was not functioning correctly. Symptoms are the same as observed on previous failing GS13s. The response of the instrument drops dramatically below 60Hz (ISI_Not_Tilted) which is characteristic of a stuck seismic mass.

This instrument was tested OK at reception from LLO. It is very likely that the tilting of the ISI induced the sticking of the seismic mass.

We have one last spare horizontal GS13 (Pod #18). It will be installed as replacement today. Testing of this unit will start over with sensor spectra, as soon as it is installed.