High Quality Content by WIKIPEDIA articles! Ionizing (or ionising) radiation is radiation composed of particles that individually carry enough energy to liberate an electron from an atom or molecule, ionizing it. Ionizing radiation is generated through nuclear reactions, either artificial or natural, by very high temperature (e.g. the corona of the Sun), or via production of high energy particles in particle accelerators, or due to acceleration of charged particles by the electromagnetic fields produced by natural processes, from lightning to supernova explosions.