Gamma Ray

A very penetrating electromagnetic ray not appreciably deflected by a magnetic or electric field emitted by radioactive substances Gamma rays are photons of electromagnetic radiation having a wavelength shorter than that of X rays i e shorter than 01 nanometer and are correspondingly more penetrating than X rays In addition to being given off in certain types of radioactive decay they may be found in cosmic radiation though they are largely absorbed by the earths atmosphere Gamma ray detectors orbited above the atmosphere have found bursts of gamma radiation in some cases associated with visually observed supernova explosions but in most cases from unidentified sources