SNO Logo The Sudbury Neutrino Observatory

Information en français

The Sudbury Neutrino Observatory (SNO) is taking data that has provided revolutionary insight into the properties of neutrinos and the core of the sun. The detector, shown in the artist's conception below, was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos.

Artist Concept of SNO

In Memoriam: Andre Hamer 1968-2003

Recent News

SNO Web Pages on This Site

SNO Web Sites at Participating Institutions

Present Status

(See the SNO Milestones for a history of past milestones achieved.)

The Sudbury Neutrino Observatory Institute (SNOI):


Dr. Tony Noble (Queen's University)
The Sudbury Neutrino Observatory Institute

Department of Physics, Stirling Hall,
Queen's University at Kingston,
Kingston, Ontario, Canada
K7L 3N6

Tel: (613) 533-2679
Fax: (613) 533-6813

The SNO Site Project Office:

SNO Operations Control Building

INCO Creighton #9 Mine
P.O. Box 159
Lively, Ontario, Canada
P3Y 1M3

Tel: (705) 692-7000
Fax: (705) 692-7001

For general information email:

URL: (Last revised Feb 24, 2003)
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