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Kamiokande
The is a neutrino and gravitational waves laboratory located underground in the Mozumi mine of the Kamioka Mining and Smelting Co. near the Kamioka section of the city of Hida in Gifu Prefecture, Japan. A set of groundbreaking neutrino experiments have taken place at the observatory over the past two decades. All of the experiments have been very large and have contributed substantially to the advancement of particle physics, in particular to the study of neutrino astronomy and neutrino oscillation. The mine The Mozumi mine is one of two adjacent mines owned by the Kamioka Mining and Smelting Co. (a subsidiary of the Mitsui Mining and Smelting Co. Mitsui Kinzoku'). The mine is famous as the site of one of the greatest mass-poisonings in Japanese history. From 1910 to 1945, the mine operators released cadmium from the processing plant into the local water. This cadmium caused what the locals called itai-itai disease. The disease caused weakening of the bones and extreme pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutrino
A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that it was long thought to be zero. The rest mass of the neutrino is much smaller than that of the other known elementary particles excluding massless particles. The weak force has a very short range, the gravitational interaction is extremely weak due to the very small mass of the neutrino, and neutrinos do not participate in the strong interaction. Thus, neutrinos typically pass through normal matter unimpeded and undetected. Weak interactions create neutrinos in one of three leptonic flavors: electron neutrinos muon neutrinos (), or tau neutrinos (), in association with the corresponding charged lepton. Although neutrinos were long believed to be massless, it is now known that there are three discrete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton Decay
In particle physics, proton decay is a hypothetical form of particle decay in which the proton decays into lighter subatomic particles, such as a neutral pion and a positron. The proton decay hypothesis was first formulated by Andrei Sakharov in 1967. Despite significant experimental effort, proton decay has never been observed. If it does decay via a positron, the proton's half-life is constrained to be at least years. According to the Standard Model, the proton, a type of baryon, is stable because baryon number (quark number) is conserved (under normal circumstances; see chiral anomaly for an exception). Therefore, protons will not decay into other particles on their own, because they are the lightest (and therefore least energetic) baryon. Positron emission and electron capture – forms of radioactive decay which sees a proton become a neutron – are not proton decay, since the proton interacts with other particles within the atom. Some beyond-the-Standard Model gran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gifu Prefecture
is a prefecture of Japan located in the Chūbu region of Honshu. Gifu Prefecture has a population of 1,991,390 () and has a geographic area of . Gifu Prefecture borders Toyama Prefecture to the north; Ishikawa Prefecture to the northwest, Fukui Prefecture and Shiga Prefecture to the west, Mie Prefecture to the southwest, Aichi Prefecture to the south, and Nagano Prefecture to the east. Gifu is the capital and largest city of Gifu Prefecture, with other major cities including Ōgaki, Kakamigahara, and Tajimi. Gifu Prefecture is located in the center of Japan, one of only eight landlocked prefectures, and features the country's center of population. Gifu Prefecture has served as the historic crossroads of Japan with routes connecting the east to the west, including the Nakasendō, one of the Five Routes of the Edo period. Gifu Prefecture was a long-term residence of Oda Nobunaga and Saitō Dōsan, two influential figures of Japanese history in the Sengoku period, spawning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Čerenkov Detector
A Cherenkov detector (pronunciation: /tʃɛrɛnˈkɔv/; Russian: Черенко́в) is a particle detector using the speed threshold for light production, the speed-dependent light output or the speed-dependent light direction of Cherenkov radiation. Fundamental A particle passing through a material at a velocity greater than that at which light can travel through the material emits light. This is similar to the production of a sonic boom when an airplane is traveling through the air faster than sound waves can move through the air. The direction this light is emitted is on a cone with angle θc about the direction in which the particle is moving, with cos(θc) = (c = the vacuum speed of light, n = the refractive index of the medium, and v is the speed of the particle). The angle of the cone θc thus is a direct measure of the particle's speed. The Frank–Tamm formula = sin2θc gives the number of photons produced. Aspects Most Cherenkov detectors aim a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kamioka, Gifu
is a city located in Gifu, Japan. , the city had an estimated population of 24,726, and a population density of 31 persons per km2, in 8,905 households. The total area of the city was . The official ''kanji'' for the city is actually 飛驒, which uses the old rendering of the 騨 character. However, the 驒 characters is not included on the official list of usable characters (as decided by the Ministry of Internal Affairs and Communications), so the 騨 character is often used outside of the city. Geography Hida is the northernmost city in Gifu Prefecture, and is located in the northern part of the Hida Highlands bordering on Toyama Prefecture to the north. The majority of the area of the city is forested, with many mountains exceeding 1,000 meters within the city borders. The northeastern edge of the Hida Mountain range exceeds 2,000 meters. Most of the population is concentrated along river terraces along the Jinzū River and the Takahara River. Climate The city has a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institute For Cosmic Ray Research
The Institute for Cosmic Ray Research (ICRR) of the University of Tokyo (東京大学宇宙線研究所 ''Tōkyōdaigaku Uchūsen Kenkyūsho'') was established in 1976 for the study of cosmic rays. The gravitational wave studies group is currently constructing the detector KAGRA located at the Kamioka Observatory. Facilities * Kashiwa Campus at the University of Tokyo * Akeno Observatory * Kamioka Observatory * Norikura Observatory Current projects *Super-Kamiokande - Detection of neutrinos and search for proton decays in a large water tank *Tibet - Search for point sources of VHE cosmic gamma rays at Tibet heights *Telescope Array Project - Aiming at highest energy cosmic ray physics by detecting weak light from atmosphere"New Ground-Based Arrays to Probe Cosmic Powerhouses" By Dennis Normile Science 30 April 1999: 734-735 *Gravitational Wave Group - Constructing the gravitational wave detector KAGRA The Kamioka Gravitational Wave Detector (KAGRA), is a large interferometer de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hida, Gifu
is a city located in Gifu, Japan. , the city had an estimated population of 24,726, and a population density of 31 persons per km2, in 8,905 households. The total area of the city was . The official ''kanji'' for the city is actually 飛驒, which uses the old rendering of the 騨 character. However, the 驒 characters is not included on the official list of usable characters (as decided by the Ministry of Internal Affairs and Communications), so the 騨 character is often used outside of the city. Geography Hida is the northernmost city in Gifu Prefecture, and is located in the northern part of the Hida Highlands bordering on Toyama Prefecture to the north. The majority of the area of the city is forested, with many mountains exceeding 1,000 meters within the city borders. The northeastern edge of the Hida Mountain range exceeds 2,000 meters. Most of the population is concentrated along river terraces along the Jinzū River and the Takahara River. Climate The city has a clim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kamioka Mining And Smelting Co
is a city located in Gifu, Japan. , the city had an estimated population of 24,726, and a population density of 31 persons per km2, in 8,905 households. The total area of the city was . The official ''kanji'' for the city is actually 飛驒, which uses the old rendering of the 騨 character. However, the 驒 characters is not included on the official list of usable characters (as decided by the Ministry of Internal Affairs and Communications), so the 騨 character is often used outside of the city. Geography Hida is the northernmost city in Gifu Prefecture, and is located in the northern part of the Hida Highlands bordering on Toyama Prefecture to the north. The majority of the area of the city is forested, with many mountains exceeding 1,000 meters within the city borders. The northeastern edge of the Hida Mountain range exceeds 2,000 meters. Most of the population is concentrated along river terraces along the Jinzū River and the Takahara River. Climate The city has a cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Ray
Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own galaxy, and from distant galaxies. Upon impact with Earth's atmosphere, cosmic rays produce showers of secondary particles, some of which reach the surface, although the bulk is deflected off into space by the magnetosphere or the heliosphere. Cosmic rays were discovered by Victor Hess in 1912 in balloon experiments, for which he was awarded the 1936 Nobel Prize in Physics. Direct measurement of cosmic rays, especially at lower energies, has been possible since the launch of the first satellites in the late 1950s. Particle detectors similar to those used in nuclear and high-energy physics are used on satellites and space probes for research into cosmic rays. Data from the Fermi Space Telescope (2013) have been interpreted as evidenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited Summit (topography), summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are Monadnock, isolated summits, but most occur in mountain ranges. Mountain formation, Mountains are formed through Tectonic plate, tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through Slump (geology), slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce Alpine climate, colder climates than at sea level at similar latitude. These colder climates strongly affect the Montane ecosystems, ecosys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Charge
Electric charge is the physical property of matter that causes charged matter to experience a force when placed in an electromagnetic field. Electric charge can be ''positive'' or ''negative'' (commonly carried by protons and electrons respectively). Like charges repel each other and unlike charges attract each other. An object with an absence of net charge is referred to as neutral. Early knowledge of how charged substances interact is now called classical electrodynamics, and is still accurate for problems that do not require consideration of quantum effects. Electric charge is a conserved property; the net charge of an isolated system, the amount of positive charge minus the amount of negative charge, cannot change. Electric charge is carried by subatomic particles. In ordinary matter, negative charge is carried by electrons, and positive charge is carried by the protons in the nuclei of atoms. If there are more electrons than protons in a piece of matter, it will have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stable Isotope
The term stable isotope has a meaning similar to stable nuclide, but is preferably used when speaking of nuclides of a specific element. Hence, the plural form stable isotopes usually refers to isotopes of the same element. The relative abundance of such stable isotopes can be measured experimentally (isotope analysis), yielding an isotope ratio that can be used as a research tool. Theoretically, such stable isotopes could include the radiogenic daughter products of radioactive decay, used in radiometric dating. However, the expression stable-isotope ratio is preferably used to refer to isotopes whose relative abundances are affected by isotope fractionation in nature. This field is termed stable isotope geochemistry. Stable-isotope ratios Measurement of the ratios of naturally occurring stable isotopes (isotope analysis) plays an important role in isotope geochemistry, but stable isotopes (mostly hydrogen, carbon, nitrogen, oxygen and sulfur) are also finding uses in ecological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
