positron

noun
pos·​i·​tron | \ ˈpä-zə-ˌträn How to pronounce positron (audio) \

Definition of positron

: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron

called also antielectron

Examples of positron in a Sentence

Recent Examples on the Web The dance between positron and antiproton in antihydrogen should exactly follow that of the electron and proton in hydrogen. Sophia Chen, Wired, "Physicists Take Their Closest Look Yet at an Antimatter Atom," 19 Feb. 2020 In contrast, the higher energies used in the ALPHA experiment slow antiprotons and positrons down enough for the particles to form atoms of antihydrogen for more in-depth study. Jonathan O'callaghan, Scientific American, "Physicists Come Closer to Answering Question of Antimatter’s Scarcity," 19 Feb. 2020 Sometimes, the photon immediately decays into an electron and a positron, which are propelled forward by the photon’s momentum and strike the detector near one another. Quanta Magazine, "Evidence of a ‘Fifth Force’ Faces Scrutiny," 7 June 2016 Richard Feynman, a young professor at Cornell, had invented a novel method to describe the behavior of electrons and photons (and their antimatter equivalent, positrons). George Johnson, SFChronicle.com, "Freeman Dyson, physicist who wrestled with moral questions, dies," 29 Feb. 2020 The electron, quark, and muon, for example, are paired with the positron, antiquark, and antimuon, respectively. Sophia Chen, Wired, "Physicists Take Their Closest Look Yet at an Antimatter Atom," 19 Feb. 2020 Bananas, which contain trace amounts of radioactive potassium, emit a positron every 75 minutes. Sophia Chen, Wired, "Physicists Take Their Closest Look Yet at an Antimatter Atom," 19 Feb. 2020 By contrast, the researchers observed that some electrons and positrons seem to be correlated in their emission direction. Chris Lee, Ars Technica, "New boson appears in nuclear decay, breaks standard model," 20 Dec. 2019 Positronium is a volatile, short-lived atom that seems kind of like hydrogen but has a positron—an antiparticle considered opposite to an electron, sometimes even called an antielectron—instead of a proton. Caroline Delbert, Popular Mechanics, "Physicist Believes He Has What It Takes to Make a Gamma Ray Laser," 9 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'positron.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of positron

1933, in the meaning defined above

History and Etymology for positron

positive + -tron (as in electron)

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Time Traveler for positron

Time Traveler

The first known use of positron was in 1933

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Statistics for positron

Last Updated

20 May 2020

Cite this Entry

“Positron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/positron. Accessed 3 Jul. 2020.

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More Definitions for positron

positron

noun
How to pronounce positron (audio)

English Language Learners Definition of positron

physics : a very small particle of matter that has a positive charge of electricity and that travels around the nucleus of an atom

positron

noun
pos·​i·​tron | \ ˈpäz-ə-ˌträn How to pronounce positron (audio) \

Medical Definition of positron

: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron

called also positive electron

More from Merriam-Webster on positron

Rhyming Dictionary: Words that rhyme with positron

Britannica.com: Encyclopedia article about positron

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