FLUID-DYNAMICAL MODEL OF HOT NUCLEI

A finite-temperature fluid-dynamical model of the nucleus has been inv estigated. The model allows for surface modes with an excitation energ y which is directly related to the surface tension. The currents assoc iated with these modes have strong transverse components. We show that , as a result of thermal fluctuations, a new sound velocity appears, w hich is not present at zero temperature, and, as a consequence, new ei genmodes also appear. While the energies are stable, when we take the limit T --> 0, the strength corresponding to these new eigenmodes tend s to zero. Electric and magnetic modes are studied. The spectrum of ex cited energies and the currents are calculated for a nucleus with mass number A = 208. The present model predicts a sizable redistribution o f transition strength when the temperature is increased.