Microscopic theory of dissipation for slowly time-dependent mean field potentials

✍ Scribed by V.P. Aleshin

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 250 KB
• Volume: 760
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/j.nuclphysa.2005.06.004

✦ Synopsis

We study the dissipation rate Q in systems of nucleons bound by a slowly time-dependent meanfield potential and slightly interacting between themselves. Starting from the many-body linear response formula we evaluate an expression for Q in terms of the pure shell-model quantities and the nucleon-nucleon collision rate Γ . The application of the classical sum rule leads then to an expression for Q in terms of the classical-path integral with the weighting function including Γ . For vanishing Γ this expression reduces to the Koonin-Randrup Knudsen-gas formula. For simplified Skyrme interactions the classical approximation for the Γ itself is obtained. In leptodermous systems the classical-path expression for Q decomposes into the wall formula and the multiple-reflection term owing to incomplete randomization of particle motion between consecutive encounters with the boundary. The mean-free path and temperature dependence of dissipation is analyzed for smallamplitude distortions of spherical cavities.