Wednesday, January 14, 2009
Here's a picture of the drill camp, where I spend much of my day. You can click on the picture to see a larger version.
Those red buildings are all shipping container sized trailers which were assembled in Madison and then shipped to Antarctica back when the IceCube project first started drilling. I work in the DCC (Drill Control Center) building, which is just to the left of those two big piles of snow on the right side of the picture.
One the left you can see some cable spools. These are the 2.5 km long communications cables which get lowered into the drilled holes. As a cable is deployed into a newly drilled hole, digital neutrino sensors are attached at regular intervals. The deployers only have around 27 hours from the time the drill is pulled out of the hole until the ice has refrozen to the point where they can't lower or raise the cable, so they have to work fairly quickly. The IceCube deployers have become experienced enough at this, so there's almost no risk of that happening. AMANDA, an earlier incarnation of the idea behind IceCube, got one of their strings stuck before it was fully lowered into the hole, rendering hundreds of thousands of dollars' worth of equipment useless. A lot of time and energy was spent modelling exactly how holes freeze, to the point where we can watch the drill going down and coming back up, and accurately forecast the "lifetime" of the hole.
The white boxy things in front are the icetop sensors at the tops of previously deployed strings. Even though those strings were deployed weeks ago, they're still not ready to be used. It takes a month or so for the hole to freeze completely, and bad things happen to the sensors if they're powered up in water, because water can short out the electronics. Fortunately, ice doesn't conduct electricity!