Elementary modes of oscillation of the whole nucleus, closely related to the normal modes of oscillation of coupled mechanical systems. Giant nuclear resonances occur systematically in most, if not all, nuclei, with oscillation energies typically in the range of 10–30 MeV. Among the best-known examples is the giant electric dipole (E1) resonance, in which all the protons and all the neutrons oscillate with opposite phase, producing a large time-varying electric dipole moment which acts as an effective antenna for radiating gamma rays.