As discussed during the 07 Jan 2022 meeting, the next cryostat run will seek the fastest radiative cooling through the following configuration choices:

• eliminate radiation leak apertures
• maximize emissivity of test mass volume
• improve conductivity to outer shield

Actions completed 14 Jan 2022

• Vent
• Cover up aperture to viewport with foil (on both shields).
• Remove foil from inner shield inner surface.
• Place outer shield directly onto cold plate (no clamping force).
  • A bit unsatisfying, because the outer shield is not flat relative to the cold plate, but the shield is resting quite firmly with only a slight wobble when pressed. As with any plane-plane contact, there are a limited number of true points of contact, and the contact area is increased somewhat by foil that is folded around the outer shield or the cold plate.
    • I would estimate the contact area at ~5% of the total area of the bottom flange.
  • 2x G10 spacer washers were dropped into the lower volume whild making this switch.
  • Note that bottom lid of outer shield is still not conductively cooled, and therefore will be approximately room temperature.
• Tidy up aluminum foil collar around bottom lid of outer shield.
• Tidy up mylar shield around conductive link after inner shield
• Pump down, cool down.
  • Pump down started at ~15:35.
  • Cool down started at 16:10.