gamma ray

noun

, Physics.

1. a photon of penetrating electromagnetic radiation gamma radiation 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.

gamma ray

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

Word History and Origins

Origin of gamma ray¹

First recorded in 1900–05

Example Sentences

Astrophysicists at the University of California, Berkeley, now argue that the axion could be discovered within seconds of the detection of gamma rays from a nearby supernova explosion.

From Science Daily

Light that reaches our telescopes ranges in wavelength from long radio waves to energetic gamma rays.

From Salon

The research team were simultaneously monitoring a source of gamma rays and seeking a fast radio burst when they spotted the object slowly flashing in the data.

From Science Daily

When cosmic rays collide with other matter and light surrounding the star, they generate gamma rays.

From Science Daily

Radiation is usually detected using semiconductor materials, such as cadmium zinc telluride, that produce an electrical response when struck by high-energy radiation such as gamma rays.

From Science Daily