Natural Production
Positrons are produced naturally in β+ decays of naturally occurring radioactive isotopes (for example, potassium-40) and in interactions of gamma quanta (emitted by radioactive nuclei) with matter. Antineutrinos are another kind of antiparticle created by natural radioactivity (β− decay). Many different kinds of antiparticles are also produced by (and contained in) cosmic rays. Recent (as of January 2011) research by the American Astronomical Society has discovered antimatter (positrons) originating above thunderstorm clouds; positrons are produced in gamma-ray flashes created by electrons accelerated by strong electric fields in the clouds. Antiprotons have also been found to exist in the Van Allen Belts around the Earth by the PAMELA module.
Read more about this topic: Antimatter
Famous quotes containing the words natural and/or production:
“Chinese were born ... with an accumulated wisdom, a natural sophistication, an intelligent naivete, and unless they were transplanted too young, these qualities ripened in them.... If ever I am homesick for China, now that I am home in my own country, it is when I discover here no philosophy. Our people have opinions and creeds and prejudices and ideas but as yet no philosophy.”
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