UNDER CONSTRUCTION
Our group is involved with 3 projects: CDMS II, XENON10, and LUX.
LUX
A bigger and better version of the XENON10 experiment, the Large Underground Xenon (LUX) Experiment presents a program for the construction and deployment of a large two-phase liquid/gas xenon dark matter detector and water shield, to be installed in 2008 at a Sanford Deep Underground Laboratory at the Homestake Mine, South Dakota.
XENON10
The detectors designed for the XENON project are similar to the CDMS detectors, but the detection medium is composed of liquid xenon instead of germanium or silicon. When a WIMP strikes a xenon nucleus, both an electrical charge and a light signal are produced. The ratio of charge to light emission is used to differentiate WIMP impacts from other types of background radiation. The proposed detectors would contain 1000 kilograms, or 1 tonne, of liquid xenon, to provide for a highly accurate event rate measurement. The first phase of the experiment, XENON10, ran with 15kg of liquid Xe in 2006 in the Gran Sasso National Lab in Italy, and has published the best WIMP exclusion limits to date.
CDMS II
The CDMS II experiment is an extension of the Cryogenic Dark Matter Search which was based at Stanford University. The second phase of this project is taking place almost half a mile beneath the earth's surface in the Soudan Mine in Minnesota. What happens is this: detectors consisting of germanium and silicon crystals are cooled to a temperature within a fraction of a degree above absolute zero. The earth, moving along its orbit, should be flying through clouds of dark matter particles, which travel straight through the earth without interacting with it. The CDMS detectors are designed to record the rare events in which a dark matter particle collides with the nucleus of an atom in the crystal. The detectors are shielded by layers of lead and a half a mile of earth and rock to keep other types of radiation from making it to the detectors and thereby corrupting the data. The CDMS II website offers a more detailed description of the experiment here.