Towards new understanding of nuclear rotation

Properties of time evolution of wave packets built up from rotator eigenstates are discussed. The mechanism of perfect cloning of the initial wave packet for "circular states" at fractional revival times is explained. The smooth transition from "circular" to "linear" through intermediate "elliptic" is described. Example of time evolution of a nuclear wave packet created in Coulomb excitation mechanism is presented.Comment: 4 pages, 2 figures, LaTeX (appb.sty included), Presented at the XXXIII Zakopane School of Physics, Zakopane, Poland, September 1-9, 1998. To appear in Acta Phys. Polon. B (1999

Geometrical properties of intelligent spin states and time evolution of coherent states

We remind the properties of the intelligent (and quasi-intelligent) spin states introduced by Aragone et al. We use these states to construct families of coherent wave packets on the sphere and we sketch the time evolution of these wave packets for a rigid body molecule.Comment: 7 pages + 4 figures (11p), LaTeX2e, Paper accepted for publication in J.Phys.A: Math.Ge