Baksan Neutrino Observatory

The Baksan Neutrino Observatory (BNO; Baksan is sometimes spelled Baxan) is a scientific laboratory of INR RAS located in the Baksan River gorge in the Caucasus mountains in Russia. Cleared for building in 1967, it started operations in 1977, becoming the first such neutrino observatory in the USSR. It consists of the Baksan Underground Scintillation Telescope (BUST), located 300 m (980 ft) below the surface, the gallium–germanium neutrino telescope (Soviet–American Gallium Experiment, SAGE) located 4,700 m.w.e.

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