Today we made the necessary preparations for cooling down the EBEX cryostat. We still had some concerns about the cryostat's pump-down rate, so we leak-checked again this morning and again found nothing untoward. It seems that our rental turbopump is just kind of slow.
Hannes spent the day installing SQUID controller boards onto the cryostat and installing all of the necessary cabling inside the RF-tight enclosure at the bottom of the cryostat. I attended our mission planning meeting with CSBF where we laid out our requirements and desires for the flight and worked on a model of the launch vehicle geometry so we can figure out how much height we have to play with.
At the end of the day, we started pre-cooling the cryostat, filling both the liquid nitrogen and liquid helium tanks with liquid nitrogen. This was uneventful, as planned, and the next day or so will be waiting for the relatively-isolated cold optics inside the cryostat to cool down.
Also, cowboy hats are awesome. I'm pretty sure I'm going to buy one tomorrow.