Soft octupole vibrations on superdeformed states in nuclei around 40Ca suggested by Skyrme-HF and self-consistent RPA calculations.

We present the results of fully self-consistent RPA calculation for low-frequency negative-parity modes built on superdeformed states in the ⁴⁰Ca region. The RPA calculation was carried out using the mixed representation on the three-dimensional Cartesian mesh in a box. The SD shell structure provides a very favorable situation for octupole shape fluctuations, and we show that the coherent excitation of protons and neutrons play an important role in the emergence of strongly collective octupole vibrations buit on the SD states in the N = Z nuclei, ³²S, ³⁶Ar, ⁴⁰Ca and ⁴⁴Ti. In particular, the calculation suggests that a low-frequency, strongly collective K^π = 1^- octupole vibration appears on the SD state in ⁴⁰Ca. [ABSTRACT FROM AUTHOR]