Role of nuclear surface vibrations in low energy heavy ion collisions

Nuclear surface vibrations cause dissipation as well as fluctuations of the relative motion between heavy ions. Viewing these as transport phenomena, we derive explicit formulae for the induced force and the correlation functions in terms of the spectrum of the nuclear vibrations and the coupling form factor. We provide a general proof that the path integral approach and the density operator formalism lead to equivalent transport coefficients as long as the influence functional takes a standard form. As an illustration, we then analyze⁸⁴Sr+²⁰⁸Pb scattering. We discuss the properties of the potential renormalization, and explain the mechanism of the high lying vibrations becoming dominant in dissipation with increasing bombarding energy by examining the properties of the retarded friction function.