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Mixed Representation RPA Calculation for Octupole Excitations on Superdeformed Sates in the 40Ca and Neutron-Rich Sulfur Regions

T. Inakura·H. Imagawa·Y. Hashimoto·S. Mizutori·M. Yamagami·K. Matsuyanagi
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Abstract

By means of the mixed representation RPA based on the Skyrme-Hartree-Fock mean field, we investigate low-frequency octupole excitations built on the superdeformed (SD) states in the N=Z nuclei around 40Ca 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 on the SD states in 32S, 36Ar, 40Ca and 44Ti. In particular, a strongly collective K^π=1^- octupole vibration is suggested to appear on top of the SD state in 40Ca. For 48,50S 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 an extremely strong octupole transition strength due to the spatially very extended structure of the particle-hole wave functions.

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T. Inakura, H. Imagawa, Y. Hashimoto, S. Mizutori, M. Yamagami, K. Matsuyanagi. 2005-12-15. Mixed Representation RPA Calculation for Octupole Excitations on Superdeformed Sates in the 40Ca and Neutron-Rich Sulfur Regions. https://doi.org/10.1016/j.nuclphysa.2006.01.008

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