CERN Accelerating science

Experiments at CERN
Title	Octupole Deformed Nuclei in the Actinide Region
Author(s)	Burke, D ; Thorsteinsen, T ; Rubio barroso, B ; Simpson, J ; Gulda, K ; Sanchez-vega, M ; Cocks, J ; Nybo, K ; Garcia borge, M ; Aas, A ; Fogelberg, B ; Honsi, J ; Smith, G ; Naumann, R ; Grant, I
Experiment	IS322
Greybook	See IS322 experiment
Approved	11 February 1993
Status	Finished
Collaboration	ISOLDE
Accelerator	CERN ISOLDE
Abstract	The aim of the present study is to investigate the limits of the "island" of octupole deformation in the mass region A=225. It is of particular importance to demonstrate experimentally the sudden disappearance of the stable octupole deformation in the presence of a well developed quadrupole field. In order to establish the upper border line the $\beta$ -decay chains of $^{227}$Rn $\rightarrow ^{227}$Fr $\rightarrow ^{227}$Ra and $^{231}$Fr $\rightarrow ^{231}$Ra $\rightarrow ^{231}$Ac were studied at PSB-ISOLDE using advanced fast timing and $\gamma$-ray spectroscopy techniques. The lifetimes of the excited states have been measured in the picosecond range using the time-delayed $\beta\gamma\gamma$(t) method.
Related document(s)	CERN-ISC-92-28  (ISC-P-32)

Contact: Tengblad, O