The nature of dark matter is one of the great mysteries in physics today, spanning astrophysics, cosmology, and particle physics. While astrophysicists search for signs of dark matter annihilation in our galactic neighborhood, and collider physicists look for indications of dark matter production in the LHC, direct detection experiments are making great strides looking for dark matter interactions in detectors deep underground. This progress comes in part from ever-larger detectors, but with the increased exposure comes an increasingly stringent limit on allowed backgrounds from natural radioactivity. The fight against these backgrounds has spawned detector technologies ranging from cryogenic semiconductors to superheated freons. I will describe the unique ways in which the leading experiments are solving the background problem, give a few new ideas to get to the next level of dark matter sensitivity, and show the importance of a diverse field of experiments, not just for discovering dark matter but for understanding the dark matter signal after a discovery is made.
Argonne Physics Division Colloquium Schedule