Multiple Coulomb Excitation of High Spin States

Abstract

Nuclear Coulomb excitation, that is the excitation of a nucleus via the electromagnetic field produced by another, swiftly passing nucleus, has been a very important tool in nuclear spectroscopy ever since the first Coulomb excitation experiment had been performed by T. Huus and Č. Zupančič in the early fifties¹. The fruitfulness of Coulomb excitation for the study of the properties of excited nuclear states is mainly due to two reasons: (i) As long as the two colliding nuclei remain well outside the range of the nuclear forces, the interaction between the two nuclei can be assumed to be purely electromagnetic. Thus the excitation process itself is theoretically well understood, in contrast to most production processes involving nuclear forces. Consequently, the cross-sections observed in Coulomb excitation measurements can be solely used to determine electromagnetic properties of the nuclear states involved in the excitation process. (ii) Coulomb excitation, on the other hand, provides also a very clean and well determined way for producing nuclei in excited states. Thus the application of standard in-beam γ-spectroscopic techniques as e.g. the Recoil-Distance, the Doppler-Shift-Attenuation and the Perturbed-Angular-Correlation methods developed to study specific properties of excited states, is very often simplified significantly by using Coulomb excitation to prepare the ensemble of excited nuclei.