Simple description of nuclear excitations in continuous spectrum

On the basis of a simple microscopic approach the properties of nuclear excitations in continuous spectrum are investigated. Self-consistent calculations of dynamical deformation parameters as a function of excitation energy (including the giant resonance region) are performed, sum rules for these parameters are formulated, the differential and integral characteristics of excitations of different multipolarities L for smooth external fields and for fields changing sharply in space are compared. The contribution of a single-particle continuum is taken into account exactly