The Astroparticle Physics Experiments (APEX) group is one of the largest astroparticle physics groups in Canada, which has, and continues to contribute to experiments that have broadened our fundamental understanding of matter in the universe. The group contributed significantly to the Sudbury Neutrino Observatory (SNO) which discovered that neutrinos, one of the most abundant known particles in the universe, have mass. This discovery was recognised in the 2015 Nobel Prize for Physics and again in 2016 with the Breakthrough Prize for Fundamental Physics. The group at Carleton is the founding institution of SNOLAB in Sudbury, the original site of the SNO experiment. SNOLAB is now home to many other low-background physics experiments.
This tradition of world leading research at Carleton continues today with involvement in two noble liquid experiments; EXO-200 and DEAP-3600. The Xenon based EXO-200 experiment, builds upon the discovery of SNO, and aims to further elucidate the nature and origin of the neutrino mass itself by measuring neutrinoless double beta decay. The DEAP-3600 experiment uses liquid argon and pulse-shape discrimination to target the detection of more exotic particles, namely dark matter which is predicted to constitute 85% of all matter in the universe.