gamma ray

American  

noun

Physics.

1. a photon of penetrating electromagnetic radiation gamma radiation emitted from an atomic nucleus.

2. a photon emitted by an electron as a result of internal conversion.

3. electromagnetic radiation with wavelengths shorter than approximately one tenth of a nanometer.

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gamma ray Scientific  

1. A stream of high-energy electromagnetic radiation given off by an atomic nucleus undergoing radioactive decay. Because the wavelengths of gamma rays are shorter than those of x-rays, gamma rays have greater energy and penetrating power than x-rays. Gamma rays are emitted by pulsars, quasars, and radio galaxies but cannot penetrate the Earth's atmosphere.

2. See more at radioactive decay

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Etymology

Origin of gamma ray

First recorded in 1900–05

Example Sentences

See Examples For:

gamma ray

Because of this, he views the data as a strong candidate for long-sought gamma ray emission from dark matter.

From Science Daily ● Nov. 29, 2025

Further support could come from finding the same gamma ray signature in other regions rich in dark matter.

From Science Daily ● Nov. 29, 2025

However, theory suggests that when two WIMPs collide, they annihilate each other and release energetic particles, including gamma ray photons.

From Science Daily ● Nov. 29, 2025

A gamma ray detector on a device developed by a Cornish company is being used to assess soil quality.

From BBC ● Nov. 26, 2024

I would very much like this to be the case but I have to recognize that there are other possible explanations for the gamma ray bursts, such as colliding neutron stars.

From "A Brief History of Time: And Other Essays" by Stephen Hawking