gamma ray


Definition of gamma ray

: a photon emitted spontaneously by a radioactive substance also : a photon of higher energy than that of an X-ray

Examples of gamma ray in a Sentence

Recent Examples on the Web The two gamma ray events were detected in July 2018 and January 2019. Ashley Strickland, CNN, "Universe's strongest explosions captured by ground telescopes for first time," 20 Nov. 2019 Bursts of gamma rays may be the key to identifying whether this primordial black hole exists. Jennifer Leman, Popular Mechanics, "If Planet 9 Is Actually a Black Hole, It Completely Changes How We Understand Our Universe," 1 Oct. 2019 Hooper and his Fermilab colleague Lisa Goodenough discovered the unexplained gamma ray glow in 2009 while studying data from NASA’s orbiting Fermi Gamma-ray Space Telescope. Adrian Cho, Science | AAAS, "Physicists revive hunt for dark matter in the heart of the Milky Way," 12 Nov. 2019 Spitzer detects infrared light, while the Hubble Space Telescope captures visible and UV light; the Compton Gamma Ray Observatory was designed for gamma rays; and the Chandra X-ray Observatory sees X-rays. Ashley Strickland, CNN, "Jack-o'-lantern Nebula grimaces on the edge of the Milky Way," 30 Oct. 2019 After analyzing publicly available data from the Fermi Gamma Ray Space Telescope, a satellite launched a year earlier, the team concluded that the center of the Milky Way was radiating more gamma rays than astrophysicists could account for. Quanta Magazine, "Galactic Glow, Thought to Be Dark Matter, Now Hints at Hidden Pulsars," 14 Nov. 2017 The near-simultaneous arrival of GW170817’s gravitational waves and gamma rays also confirmed the prediction made by Einstein that gravitational waves would travel at the speed of light. The Economist, "Gravitational astronomy proves its maturity," 22 Aug. 2019 Creating gamma ray photons obviously takes a lot of energy. Chris Lee, Ars Technica, "Gamma ray evidence for dark matter outshone by a flock of pulsars," 10 Aug. 2018 Telescopes capable of examining all parts of the spectrum, from gamma rays to radio waves, were brought into play. The Economist, "Gravitational astronomy proves its maturity," 22 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gamma ray.' 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 gamma ray

1903, in the meaning defined above

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Time Traveler for gamma ray

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The first known use of gamma ray was in 1903

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Statistics for gamma ray

Last Updated

3 Dec 2019

Cite this Entry

“Gamma ray.” The Dictionary, Merriam-Webster Inc., Accessed 5 December 2019.

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More Definitions for gamma ray

gamma ray

gam·​ma ray | \ ˈga-mə- \

Kids Definition of gamma ray

: a ray that is like an X-ray but of higher energy and that is given off especially by a radioactive substance

gamma ray


Medical Definition of gamma ray

: a photon emitted spontaneously by a radioactive substance also : a high-energy photon usually used in plural

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More from Merriam-Webster on gamma ray

Rhyming Dictionary: Words that rhyme with gamma ray

Spanish Central: Translation of gamma ray

Nglish: Translation of gamma ray for Spanish Speakers Encyclopedia article about gamma ray

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