1 positron | Definition of positron

positron

noun
pos·​i·​tron | \ ˈpä-zÉ™-ËŒträn 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

That hypothesis is based on studies in which the pair used positron emission tomography (PET) imaging, which uses radioactive labels to track neurotransmitters, to capture serotonin levels in the brain. Emily Underwood, Science | AAAS, "Brain scans could help personalize treatment for people who are depressed or suicidal," 20 Aug. 2019 If the electrons and positrons had originated from persistent rho particles with a characteristic energy or mass, there would have been a bump in the curve. Quanta Magazine, "Physicists Peer Inside a Fireball of Quantum Matter," 30 July 2019 In a paper published in the May 2019 issue of Medical Image Analysis, MSK investigators, led by medical physics researcher Ida Häggström, detail a new method of image reconstruction for positron emission tomography, or PET . Julie Grisham, Scientific American, "Faster, clearer PET images offer new views on disease," 9 July 2019 Like the sun on a bad day, this young magnetar releases occasional flares that blast out electrons, positrons and maybe heavier ions at near the speed of light. Joshua Sokol, WIRED, "Astronomers Think They Can Explain Mysterious Cosmic Bursts," 10 Mar. 2019 These radiotracers decay via positron emission, creating back-to-back gamma rays that are simultaneously detected by a PET scanner. Julie Grisham, Scientific American, "Faster, clearer PET images offer new views on disease," 9 July 2019 The first stage will see the FCC collide electrons with positrons, the antimatter electron counterpart. Avery Thompson, Popular Mechanics, "Scientists Are Planning a New Particle Collider That Absolutely Dwarfs the LHC," 16 Jan. 2019 Electrons can then be added to create an electron-positron plasma. Chris Lee, Ars Technica, "Technical tour-de-force traps positrons," 11 Dec. 2018 When excited, an atom can absorb a third photon, which strips away its positron entirely. Adrian Cho, Science | AAAS, "Atoms and antiatoms haven’t crashed Albert Einstein’s theory of relativity—yet," 4 Apr. 2018

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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More Definitions for positron

positron

noun

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-É™-ËŒträn 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