Gamma rays typically have energies above 100 k eV, and therefore have frequencies above 10 exahertz (or > 10 Hz) and wavelengths less than 10 picometers (10 m), which is less than the diameter of an atom. However, this is not a strict definition, but rather only a rule - of - thumb description for natural processes. Electromagnetic radiation from radioactive decay of atomic nuclei is referred to as "gamma rays '' no matter its energy, so that there is no lower limit to gamma energy derived from radioactive decay. This radiation commonly has energy of a few hundred keV, and almost always less than 10 MeV. In astronomy, gamma rays are defined by their energy, and no production process needs to be specified. The energies of gamma rays from astronomical sources range to over 10 TeV, an energy far too large to result from radioactive decay. A notable example is the extremely powerful bursts of high - energy radiation referred to as long duration gamma - ray bursts, of energies higher than can be produced by radioactive decay. These bursts of gamma rays are thought to be due to the collapse of stars called hypernovae.
what is the wavelength of a gamma ray
less than 10 picometers (10 m)