X-rays 21
X-rays 21 : Radiation and Radiological Disasters. Penetrating electromagnetic radiation (photon) having a wavelength that is much shorter than that of visible light. Rays produced by excitation of the electron field around certain nuclei are called characteristic x-rays. In nuclear reactions, it is customary to refer to photon originating in the nucleus as gamma rays, and to those originating in the electron field of the atom as X-rays