Secretary notes from BSC9 today:
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The chamber door was pulled by Gerardo/Kyle/Bubba.
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~20 mins later, with the billowing C3 door cover on, I reached in and took particle counter counts of 30 - 0.3um, 20 - 0.5um, 10 - 0.7um. A pretty clean sample.
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I reached in an wiped ~2/3 of the floor.
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Jim locked the HEPI.
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Jim locked the ISI.
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Travis, Jason and I went into the chamber.
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We attached the locking bracket to the ACB and let it swing back to it's natural hanging position, giving us a bit of room to work, yet not occulting the pcal camera view.
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We removed the vertical witness plate that was hanging from the bottom of QUAD structure.
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We inspected the ETMx-HR - We saw no dead-ringer particle that was a more obvious "scatterer" than any other particles on the surface of the mirror. We also did not see any large bits of left over FirstContact or other debris. We put the green lantern onto the suspension structure and counted ~5-10 particles per sq. inch roughly everywhere in the central 8" circle area of the mirror - higher than what we counted on the ETMy. We spent a few minutes blowing with the deionizing N2 Top Gun blower - not much moved.
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We decided we should FC clean the surface given that the particle count level was higher than the ETMy level, even though we did not find the one we were looking for. We also noticed that more particulate was floating around in the flashlight beams than we noticed at ETMy. See my particle count data below, though.
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Rick took quite a few pictures of the surface in an attempt to capture the particulate condition - pictures will be available tomorrow when we post final results.
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We clamped the optic with the TFE rail tooling.
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We applied brush-on FC in the same manner as yesterday (thick short dabs/strokes, 3 coats) and put the PETG cap on.
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WE wiped more of the floor.
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We removed all of the extra tooling/blow gun/lights from the chamber and exited for the day.
We will pull the FC sheet ~9:30 am tomorrow and hopefully get the door back on by lunch.
Note, there were apparently no witness plate or witness optics placed on the floor of BSC9 when it was closed last time, so we did not pick them up today.
Also, I forgot to mention that when we inspected the ETMx-HR, we saw some mottling and haze across the surface but we did NOT see the "ring" feature that the FC left on the ETMy-HR.