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

For every simulation, the researchers calculated both neutrino production and the related gamma ray emission, then compared the results with real observations.

From Science Daily ● May 24, 2026

The emitted gamma rays were detected with GRETINA, a high resolution germanium detector array capable of tracking individual gamma ray interactions.

From Science Daily ● Mar. 8, 2026

The estimated frequency of these annihilation events based on the observed gamma ray intensity also fits within expected theoretical ranges.

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