RPA calculations with Gaussian expansion method

Abstract

The Gaussian expansion method (GEM) is extensively applied to the calculations in the random-phase approximation (RPA). We adopt the mass-independent basis-set that has been tested in the mean-field calculations. By comparing the RPA results with those obtained by several other available methods for Ca isotopes, using a density-dependent contact interaction and the Woods-Saxon single-particle states, we confirm that energies, transition strengths and widths of their distribution are described by the GEM bases to good precision, for the $1^{-}$, $2^{+}$ and $3^{-}$ collective states. The GEM is then applied to the self-consistent RPA calculations with the finite-range Gogny D1S interaction. The spurious center-of-mass motion is well separated from the physical states in the $E1$ response, and the energy-weighted sum rules for the isoscalar transitions are fulfilled reasonably well. Properties of low-energy transitions in ${}^{60}$Ca are argued in some detail.

30 pages including 12 figures

References in corpus (5)

• Role of deformation on giant resonances within the QRPA approach and the Gogny force
• Pygmy dipole strength in 90Zr
• Self-consistent description of multipole strength: systematic calculations
• Effects of self-consistency violation in Hartree-Fock RPA calculations for nuclear giant resonances revisited
• Application of Gaussian expansion method to nuclear mean-field calculations with deformation

Cited by in corpus (12)

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• Self-consistent Continuum Random Phase Approximation calculations with finite-range interactions
• Shell structure in neutron-rich Ca and Ni nuclei under semi-realistic mean fields
• Modified parameter-sets of M3Y-type semi-realistic nucleon-nucleon interaction for nuclear structure studies
• Fine structure of the isoscalar giant quadrupole resonance in 40Ca due to Landau damping?
• Properties of exotic nuclei and their linkage to the nucleonic interaction
• The quest for novel modes of excitation in exotic nuclei
• Constraining slope parameter of symmetry energy from nuclear structure
• Crossover from skin-mode to proton-neutron-mode in $E1$ excitations of neutron-rich nuclei
• Pairing in spherical nuclei: quasi-particle random phase approximation calculations with the Gogny interaction