Grant: Subatomic Physics Envelope - Project

In contrast to our perception, most of the matter in the universe is not composed of atoms, but rather consists of a yet unidentified type of elementary particle. These particles do not emit or absorb light or other electromagnetic radiation, giving rise to the term Dark Matter. So far all our knowledge about dark matter is based on its gravitational effects at astronomical scales. Interactions of individual dark matter particles with ordinary matter could tell us about the nature of these particles, but they happen very rarely if at all. The Cryogenic Dark Matter Search (CDMS) collaboration has developed extremely sensitive detectors in an attempt to detect such interactions. These detectors are operated close to the lowest physically possible temperature and are able to distinguish between these potential interactions and those of the much more common environmental radiation with high efficiency. The successor experiment, SuperCDMS, is starting its operation in 2011 at a ~700 m deep underground laboratory in Soudan, Minnesota., but its sensitivity will eventually be limited by residual cosmic radiation which can still penetrate to this depth. We are therefore planning the next phase of the experiment at SNOLAB, which is a new and much deeper laboratory (2000 m underground) near Sudbury, Ontario. The Canadian effort in SuperCDMS is focused on the preparation of the SNOLAB phase of the experiment. As a first step towards the move we are installing a well shielded cryogenic detector testing facility at SNOLAB. This will be the only facility in the SuperCDMS collaboration of more than 80 scientists from 18 mostly US institutions where the performance of the new generation of detectors being developed for the SNOLAB phase can be fully demonstrated. With support from NSERC we will operate this and the existing test facility at Queen's to further the detector development for SuperCDMS at SNOLAB which eventually may enable us to detect dark matter. This would not only solve a long standing mystery, but also put Canada in the centre of the map of fundamental science.