SNOLAB is an underground science laboratory located two km below the surface in the Vale Creighton Mine located near Sudbury, Ontario, Canada. The site is off the north shore of Lake Huron, approximately 400 km northwest of Toronto. SNOLAB is an expansion of the existing facilities constructed for the Sudbury Neutrino Observatory (SNO) solar neutrino experiment. The project was jointly proposed by Carleton University, Laurentian University, Queen's University, the University of British Columbia, the University of Guelph and the Universite de Montreal. Including the existing SNO facilities, SNOLAB has 5,000 m2 of clean space underground for experiments and the supporting infrastructure; on surface there is a 3,100 m2 building constructed on the Creighton mine site to support the underground experiments. At nearby Laurentian University there is a facility for radio-isotope measurements and water analysis. Excavation of the underground laboratory expansion began in 2004 and SNOLAB celebrated the official Grand Opening of the laboratory in May 2012.
SNOLAB follows on the important achievements in neutrino physics achieved by SNO and other underground physics measurements. The primary scientific emphasis at SNOLAB will be on astroparticle physics with the principal topics being:
- Low Energy Solar Neutrinos
- Neutrinoless Double Beta Decay
- Cosmic Dark Matter Searches
- Supernova Neutrino Searches
These are fields where the next generation of experiments require great depths to reduce cosmogenic backgrounds to acceptable levels. They also require extreme levels of cleanliness to reduce environmental radiological backgrounds to the levels necessary for these very sensitive measurements. SNOLAB achieves these goals by being located 2 km underground and by having the entire laboratory constructed as a single large clean room (class 2000).
While particle astrophysics is the principle focus for SNOLAB, there is a growing interest in other scientific fields to exploit deep underground laboratories and their associated infrastructure. In particular, there has been interest expressed in the fields of Seismology and Geophysics interested in precision, long term measurements at depth and in the field of Biology where there is a growing interest in deep under ground life.