Super-Kamiokande, or Super-K for short, is a neutrino observatory in Japan. A neutrino detector is a device designed to detect Neutrinos Because neutrinos are very weakly interacting neutrino detectors must be very large in order to detect a significant For a topic outline on this subject see List of basic Japan topics. The observatory was designed to search for proton decay, study solar and atmospheric neutrinos, and keep watch for supernovas in the Milky Way Galaxy. In Particle physics, proton decay is a hypothetical form of Radioactive decay in which the Proton decays into lighter Subatomic particles neutrino]]s are produced in the Sun as a product of Nuclear fusion. Neutrinos are Elementary particles that travel close to the Speed of light, lack an Electric charge, are able to pass through ordinary matter almost A supernova (plural supernovae or supernovas) is a stellar Explosion. The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias sometimes referred to simply
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. is the northernmost city in Gifu Prefecture, Japan. It received its name from the historical province of Hida Province, which was centered around the same area WikipediaWikiProject Japanese prefectures for guidelines--> is a prefecture located in the Chūbu region of central Japan. For a topic outline on this subject see List of basic Japan topics. 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. Water is a common Chemical substance that is essential for the survival of all known forms of Life. 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. Photomultiplier tubes ( photomultipliers or PMT s for short members of the class of Vacuum tubes and more specifically Phototubes are extremely There is a barrier that optically separates the ID and OD.
A neutrino interaction with the electrons or nuclei of water can produce a charged particle that moves faster than the speed of light in water (although of course slower than the speed of light in vacuum). The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. This creates a cone of light known as Cherenkov radiation, which is the optical equivalent to a sonic boom. Čerenkov radiation (also spelled Cerenkov or Cherenkov) is Electromagnetic radiation emitted when a charged particle (such as an The term sonic boom is commonly used to refer to the shocks caused by the Supersonic flight of an aircraft The Cherenkov light is projected as a ring on the wall of the detector and recorded by the PMTs. Using the timing and charge information recorded by each PMT, the interaction vertex, ring direction and flavor of the incoming neutrino is determined. From the sharpness of the edge of the ring the type of particle can be inferred. The multiple scattering of electrons is large, so electromagnetic showers produce fuzzy rings. Scattering is a general physical process whereby some forms of Radiation, such as Light, Sound or moving particles for example are forced to deviate from Highly relativistic muons, in contrast, travel almost straight through the detector and produce rings with sharp edges. Special relativity (SR (also known as the special theory of relativity or STR) is the Physical theory of Measurement in Inertial The muon (from the letter mu (μ--used to represent it is an Elementary particle with negative Electric charge and a spin of 1/2
History
Construction of Kamioka Underground Observatory, the predecessor of the present Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo began in 1982 and was completed in April, 1983. The is a Neutrino Physics Laboratory located underground in the Mozumi Mine of the Kamioka Mining and Smelting Co The Institute for Cosmic Ray Research (ICRR of the University of Tokyo (東京大学宇宙線研究所 Tōkyōdaigaku Uchūsen Kenkyūjo) was established in 1976 The, abbreviated as, is a major Research university located in Tokyo, Japan. Year 1982 ( MCMLXXXII) was a Common year starting on Friday (link displays the 1982 Gregorian calendar) Year 1983 ( MCMLXXXIII) was a Common year starting on Saturday (link displays the 1983 Gregorian calendar) The purpose of the observatory was to detect whether proton decay exists, one of the most fundamental questions of elementary particle physics.
The detector, named KamiokaNDE for Kamioka Nucleon Decay Experiment, was a tank 16. Chemical tanks are storage Containers for Chemicals They come in a variety of sizes and shapes and are used for Static storage mixing and transport 0m in height and 15. 6m in width, containing 3,000 tons of pure water and about 1,000 photomultiplier tubes (PMTs) attached to its inner surface. The detector was upgraded, starting in 1985, to allow its to observe solar neutrinos. Year 1985 ( MCMLXXXV) was a Common year starting on Tuesday (link displays 1985 Gregorian calendar) As a result, the detector (KamiokaNDE-II) had become sensitive enough to detect neutrinos from SN 1987A, a supernova which was observed in the Large Magellanic Cloud in February 1987, and to observe solar neutrinos in 1988. SN 1987A was a Supernova in the outskirts of the Tarantula Nebula in the Large Magellanic Cloud, a nearby A supernova (plural supernovae or supernovas) is a stellar Explosion. The Large Magellanic Cloud (LMC is a nearby Satellite galaxy of our own galaxy the Milky Way. Year 1987 ( MCMLXXXVII) was a Common year starting on Thursday (link displays 1987 Gregorian calendar) Year 1988 ( MCMLXXXVIII) was a Leap year starting on Friday (link displays 1988 Gregorian calendar) The ability of the Kamiokande experiment to observe the direction of electrons produced in solar neutrino interactions allowed experimenters to directly demonstrate for the first time that the sun was a source of neutrinos. In Scattering theory and in particular in Particle physics, elastic scattering is one of the specific forms of scattering
Despite successes in neutrino astronomy and neutrino astrophysics, Kamiokande did not achieve its primary goal, the detection of proton decay. Neutrino astronomy is the branch of astronomy that observes astronomical objects with neutrino detectors in special observatories Higher sensitivity was also necessary to obtain high statistical confidence in its results. This led to the construction of Super-Kamiokande, with fifteen times the water and ten times as many PMTs as Kamiokande. Super-Kamiokande started operation in 1996. Year 1996 ( MCMXCVI) was a Leap year starting on Monday (link will display full 1996 Gregorian calendar)
The Super-Kamiokande Collaboration announced the first evidence of neutrino oscillation in 1998. Neutrino oscillation is a quantum mechanical phenomenon predicted by Bruno Pontecorvo whereby a Neutrino created with a specific Lepton Year 1998 ( MCMXCVIII) was a Common year starting on Thursday (link will display full 1998 Gregorian calendar) This was the first experimental observation consistent with the theory that the neutrino has non-zero mass, a possibility that theorists had speculated about for years. Mass is a fundamental concept in Physics, roughly corresponding to the Intuitive idea of how much Matter there is in an object
On November 12, 2001, about 6,600 of the photomultiplier tubes in the Super-Kamiokande detector imploded, apparently in a chain reaction as the shock wave from the concussion of each imploding tube cracked its neighbours. Events 764 - Tibetan troops occupy Chang'an, the capital of the Chinese Tang Dynasty, for fifteen days Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar. Implosion is a process in which objects are destroyed by collapsing in on themselves A chain reaction is a sequence of Reactions where a reactive product or by-product causes additional reactions to take place For the music album by Converter see Shock Front For the 1977 horror film see Shock Waves A shock wave (also called The detector was partially restored by redistributing the photomultiplier tubes which did not implode, and by adding protective acrylic shells that are hoped would prevent another chain reaction from recurring (SuperKamiokande-II). Poly(methyl methacrylate ( PMMA) or poly(methyl 2-methylpropenoate is a Thermoplastic and transparent Plastic.
In July 2005, preparations began to restore the detector to its original form by reinstalling about 6,000 PMTs. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. It was completed in June 2006. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. (SuperKamiokande-III)
See also
External links
- The official Super-Kamiokande home page
- American Super-K home page
- Pictures and illustrations
- Details about the accident on November 12, 2001
- Official report on the accident (in PDF format)
- Logbook entry of first neutrinos seen at Super-K generated at KEK
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic