BSC2
After respraying the BS optic with FC yesterday, we successfully pulled the FC sheets from both HR and AR surfaces of the the BS optic. After N2 blowing and some spot cleaning, we estimate particulate concentrations of 5-10 particles per square inch. We then reinstalled the elliptical baffles which had been removed for FC application, unlocked the SUS, and Jim unlocked the ISI. Quick TFs on the SUS were ran and approved, witness plate situated, and we moved to BSC1.
BSC1
The FC sheet removal from the external surfaces of ITMy went without issue. After N2 blowing, we estimate particulate concentrations of 5-10 particles per square inch on the external surfaces of both optics, and a factor of 2-3 higher on the internal surfaces. We unlocked both chains, Jim unlocked the ISI, quick TFs on the SUS ran and approved, witness plate and 1" optic installed, Betsy wiped her way out of chamber, and we handed it over to Apollo for door installation.
Particle count measurements were taken in BSC 1 and 2 numerous times during the ~2 hours of First Contact removal and chamber closeout on Friday. First Contact was pulled on the BS HR and AR surfaces around 12:30pm. FC was pulled on the ITMy HR, CP-AR around 1:45pm. BSC1 door was attached to chamber around 2:30.
Counts were always around:
0.3um ~200
0.5um ~60