 Nuclear excited state

A nuclear excited state lies above the same nucleus's ground state in internal energy. spin, parity and approximate isospin help classify it. Single-particle rearrangements, broken pairs and collective deformation/vibration give different excitation patterns and can mix. Below particle-emission thresholds, gamma decay and internal conversion are important de-excitation routes; an excitation energy is not necessarily the energy of every emitted gamma ray in a cascade.