Information AboutPositron |
| CATEGORIES ABOUT POSITRON | |
| fundamental physics concepts | |
| leptons | |
| antimatter | |
| quantum electrodynamics | |
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]]The positron is the Antiparticle or the Antimatter counterpart of the Electron . The positron has an Electric Charge of +1, a Spin of 1/2, and the same mass as an electron. When a low-energy positron Annihilate s with an electron, their mass is converted into the kinetic Energy of two Gamma Ray Photon s (See Electron-positron Annihilation .). A positron may be generated by Positron Emission radioactive decay, or the interaction of Photon with a charged particle (such as an atom's nucleus) with energy greater than 2''m''e''c''2 = 2×0.511 MeV = 1.022 MeV with matter (''m''e is the mass of one electron and ''c'' is the Speed Of Light in vacuum). This process is called Pair Production , as it generates one electron and one positron from the energy of the photon. The existence of positrons was first postulated in 1928 by Paul Dirac as an inevitable consequence of the Dirac Equation . In 1932, positrons were observed by Carl D. Anderson , who gave the positron its name. Anderson also unsuccessfully suggested renaming Electrons "negatrons." The positron was the first evidence of Antimatter and was discovered by passing Cosmic Ray s through a gas chamber and a lead plate surrounded by a magnet to distinguish the particles by bending differently charged particles in different directions. Today, positrons are produced in enormous numbers in accelerator physics laboratories and used in Electron-positron Collider s. THE POSITRON IN FICTION The most famous use of the positron in fiction was Isaac Asimov 's use in his Robot s' Positronic Brain s. It is likely that he chose to use positrons because they were relatively newly-discovered when he was first writing about the robots. Perhaps in an homage to Asimov, in the Star Trek universe the Android Data , his "brother" Lore , "daughter" Lal , and other sundry related androids also have positronic brains. In , is used to defeat the invading Angels on numerous occasions. In the Japan ese Anime sci-fi series '' Mobile Suit Gundam SEED '' and its Sequel , '' Mobile Suit Gundam SEED Destiny '', large-scale positron cannons are used on some advanced warships for space-faring combat. Some characters in the series have moral issues with the use of positron cannons within the Earth's Atmosphere , as the Gamma Radiation produced by annihilation reactions can irradiate the surrounding environment in the same way as a nuclear explosion, causing Cancer s and mutations. SEE ALSO EXTERNAL LINKS
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