Super-Kamiokande

Super-Kamiokande, or Super-K for short, is a neutrino observatory in Japan. The observatory was designed to search for proton decay, study solar and atmospheric neutrinos, and keep watch for supernovas in the Milky Way Galaxy.Super-K is located 1,000 m underground in the Mozumi Mine (Kamioka Mining and Smelting Co.) in Hida city (formerly Kamioka town), Gifu, Japan. The detector consists of a cylindrical stainless steel tank 41.4 m tall and 39.3 m in diameter enclosing 50,000 tons of ultra-purified water. The tank volume is divided by a stainless steel superstructure into an inner detector (ID) region that is 33.8 m in diameter and 36.2 m in height and outer detector (OD) which consists of the remaining tank volume. Mounted on the superstructure are 11,146 photomultiplier tubes (PMT) 20 inches in diameter that face the ID and 1885 8-inch PMTs that face the OD. There is a barrier that optically separates the ID and OD.
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