1. The act or process of being put into motion or stimulation: Rachel's two little boys had excitations when she told them they could eat their lunch now.
2. The activity produced in a bodily organ, tissue, or part; such as, a nerve cell, as a result of some kind of stimulation: Kate had some excitations after her medical treatment of pains in her knee joints and how much better she felt when she went for walks.

1. The existence of a high-energy state within a nucleus, arising from the interaction of the nucleus and bombarding particles too weak to penetrate it.
2. Nuclear excitation caused by the time-dependent long-ranged electric field acting between colliding nuclei.

Theoretically, the Coulomb force between the positively charged colliding nuclei is well understood, and the interaction is calculable exactly.

Coulomb excitation usually is the dominant reaction in nuclear scattering, and even occurs at low bombarding energies where the separation of the nuclei is sufficiently large that the short-ranged nuclear force does not act.