Mixed representation RPA calculation for octupole excitations on superdeformed states in the Ca-40 and neutron-rich sulfur regions

摘要

By means of the mixed representation RPA based on the Skyrme-Hartree-Fock mean field, we investigate low-frequency octupole excitations built oil the superdeformed (SD) states in the N = Z nuclei around Ca-40 and the neutron-rich sulfur isotopes. The RPA calculation is carried out fully self-consistently on the three-dimensional Cartesian mesh in a box, and yields a number of low-frequency octupole vibrations built oil the SD states in (32)s, Ar-36, Ca-40 and Ti-44. In particular, a strongly collective K-pi = 1(-) octupole vibration is suggested to appear on top of the SD state in Ca-40. For S-48,S-50 close to the neutron drip line, we find that the low-lying state created by the excitation of a single neutron from a loosely bound low Omega level to a high Omega resonance level acquires ail extremely strong octupole transition strength due to the spatially very extended structure of the particle-hole wave functions. (c) 2006 Elsevier B.V. All rights reserved.