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

Using rare isotope beams at Michigan State University and highly sensitive gamma ray detectors, the team measured the lifetimes of excited nuclear states with precision on the scale of picoseconds.

From Science Daily ● Mar. 8, 2026

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

The measured gamma ray energy spectrum, which describes how the intensity of the emission varies, closely matches model predictions for the annihilation of hypothetical WIMPs with masses roughly 500 times that of a proton.

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

But despite the close agreement in position Helfand and Long do not insist that the gamma ray outburst is associated with the supernova remnant.

From "Cosmos" by Carl Sagan