Radiative decay is a process in which an excited atom or molecule releases energy in the form of electromagnetic radiation, such as light or gamma rays, as it returns to its ground state. This process is fundamental in the study of atomic and molecular physics, as it allows scientists to understand the electronic structure and energy levels of atoms and molecules. Radiative decay is a key process in various fields, including spectroscopy, quantum mechanics, and astrophysics, and is used in a wide range of applications such as fluorescence imaging, laser technology, and nuclear medicine.