Isovector response function of hot nuclear matter with Skyrme interactions

Abstract

We investigate the role of the effective nucleon-nucleon interaction in the description of giant dipole resonances in hot nuclei. For this purpose we calculate the response function of hot nuclear matter to a small isovector external perturbation using various effective Skyrme interactions. We find that for Skyrme forces with an effective mass close to unity an undamped zero sound mode occurs at zero temperature. This mode gives rise in finite nuclei (calculated via the Steinwedel-Jenssen model) to a resonance whose energy agrees with the observed value. We find that zero sound disappears at a temperature of a few MeV, leaving only a broad peak in the dipole strength. For Skyrme forces with a small value of the effective mass (0.4- 0.5), there is no zero sound at zero temperature but only a weak peak located too high in energy. The strength distribution in this case is nearly independent of temperature and shows small collective effects. The relevance of these results for the saturation of photon multiplicities observed in recent experiments is pointed out.

33 pages Email: [email protected]

References in corpus (1)

• Response Function of Hot Nuclear Matter

Cited by in corpus (19)

• Surface Symmetry Energy of Nuclear Energy Density Functionals
• Linear response theory and neutrino mean free path using Brussels-Montreal Skyrme functionals
• Linear response of homogeneous nuclear matter with energy density functionals
• Neutrino propagation and spin zero sound in hot neutron matter with Skyrme interactions
• Cluster formation in asymmetric nuclear matter: semi-classical and quantal approaches
• General response function for interacting quantum liquids
• Nuclear response for the Skyrme effective interaction with zero-range tensor terms. III. Neutron matter and neutrino propagation
• Isovector Vibrations in Nuclear Matter at Finite Temperature
• Linear response theory in asymmetric nuclear matter for Skyrme functionals including spin-orbit and tensor terms
• Linear Response Theory with finite-range interactions
• Nuclear matter symmetry energy from generalized polarizabilities: dependences on momentum, isospin, density and temperature
• Quasiparticle parameterization of meanfields, Galilei invariance and universal conserving response functions
• Dynamical response functions in correlated fermionic systems
• Isospin and density dependences of nuclear matter symmetry energy coefficients II
• Isospin dependence of nuclear matter symmetry energy coefficients
• Temperature dependence of nuclear matter generalized isovector symmetry energy with Skyrme-type interactions
• Evaluation of the escape widths of the giant dipole resonances in the fermi-liquid theory
• Shape fluctuations in a Fermi system with nonlinear dissipativity
• Isovector response and energy-weighted sums in hot nuclei