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positron

[poz-i-tron] /ˈpɒz ɪˌtrɒn/
noun, Physics.
1.
an elementary particle having the same mass and spin as an electron but having a positive charge equal in magnitude to that of the electron's negative charge; the antiparticle of the electron.
Origin
1930-1935
1930-35; posi(tive) + (elec)tron
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples for positron
  • The electron's antimatter counterpart, known as a positron, carries a positive charge.
  • The photograph is a record of the radiation given off in the electron-positron annihilations.
  • Now take an electron and the positron, think of them as mirror image's of each other.
  • There is no further discussion of the detected positron source.
  • Smash a positron and an electron and you get two or more gamma rays.
  • When a positron encounters its regular opposite, an electron, both are destroyed in a shower of new particles.
  • The result is that the electron shadow and the positron shadow are separated.
  • The collision converts the proton into a positron, the antimatter counterpart of an electron, and a recoiling neutron.
  • For example, a powerful electric field can generate electron-positron pairs in a vacuum.
  • Sodium-22 is a positron-emitting isotope with a remarkably long half-life.
British Dictionary definitions for positron

positron

/ˈpɒzɪˌtrɒn/
noun
1.
(physics) the antiparticle of the electron, having the same mass but an equal and opposite charge. It is produced in certain decay processes and in pair production, annihilation occurring when it collides with an electron
Word Origin
C20: from posi(tive + elec)tron
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for positron
n.

1933, coined from posi(tive) (elec)tron.

Online Etymology Dictionary, © 2010 Douglas Harper
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positron in Medicine

positron pos·i·tron (pŏz'ĭ-trŏn')
n.
A positively charged particle of the same mass and magnititude of charge as an electron. Also called antielectron, positive electron.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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positron in Science
positron
  (pŏz'ĭ-trŏn')   
The antiparticle that corresponds to an electron. Also called antielectron.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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positron in Culture
positron [(poz-i-tron)]

The antiparticle for an electron; it has the same mass as an electron, but carries a positive charge.

Note: Positrons are found in collisions initiated by cosmic rays.
The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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