1998/02/28 by Uwe Fuhrmann, U. Fuhrmann, Klaus Morawetz +3 · 1 citation
Physics and Astronomy · #Advanced Chemical Physics Studies #Cold Atom Physics and Bose-Einstein Condensates #Quantum, superfluid, helium dynamics #nucl-th
paper · pdf · doi:10.1103/physrevc.58.1473
published as Phys.Rev.C58:1473-1487,1998 · 15 pages, 12 figures, LaTeX, psfig.sty, revtex.sty, some new results in sec.III C, corrected some misprints
arxiv created 1998/05/08 · openalex publication_date 1998/09/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The damping rate of hot giant dipole resonances (GDRs) is investigated. Besides Landau damping we consider collisions and density fluctuations as contributions to the damping of GDRs. Within the nonequilibrium Green's function method we derive a non-Markovian kinetic equation. The linearization of the latter one leads to complex dispersion relations. The complex solution provides the centroid energy and the damping width of giant resonances. The experimental damping widths are the full width half maximum and can be reproduced by the full width of the structure function. Within simple finite size scaling we give a relation between the minimal interaction strength which is required for a collective oscillation and the cluster size. We investigate the damping of giant dipole resonances within a Skyrme type of interaction. Different collision integrals are compared with each other in order to incorporate correlations. The inclusion of a conserving relaxation time approximation allows us to find the T2 dependence of the damping rate with a temperature known from Fermi-liquid theory. However, memory effects turn out to be essential for a proper treatment of the damping of collective modes. We derive a Landau-like formula for the one-particle relaxation time similar to the damping of zero sound.