Coulomb excitation of Na-29,Na-30: Mapping the borders of the island of inversion

Summary, in English

Nuclear shell evolution in neutron-rich Na nuclei around N = 20 was studied by determining reduced transition probabilities, i.e., B(E2) and B(M1) values, in order to map the border of the island of inversion. To this end Coulomb-excitation experiments, employing radioactive Na-29,Na-30 beams with a final beam energy of 2.85 MeV/nucleon, were performed at REX-ISOLDE, CERN. De-excitation gamma rays were detected by the MINIBALL gamma-ray spectrometer in coincidence with scattered particles in a segmented Si detector. Transition probabilities to excited states were deduced. The measured B(E2) values agree well with shell-model predictions, supporting the idea that in the Na isotopic chain the ground-state wave function contains significant intruder admixture already at N = 18, with N = 19 having an almost pure two-particle-two-hole deformed ground-state configuration.

• Author: M. Seidlitz; P. Reiter; R. Altenkirch; B. Bastin; C. Bauer; A. Blazhev; N. Bree; B. Bruyneel; P. A. Butler; Joakim Cederkäll; T. Davinson; H. De Witte; Douglas DiJulio; J. Diriken; L. P. Gaffney; K. Geibel; G. Georgiev; R. Gernhaeuser; M. Huyse; N. Kesteloot; T. Kroell; R. Kruecken; R. Lutter; J. Pakarinen; F. Radeck; M. Scheck; D. Schneiders; B. Siebeck; C. Sotty; T. Steinbach; J. Taprogge; P. Van Duppen; J. Van de Walle; D. Voulot; N. Warr; F. Wenander; K. Wimmer; P. J. Woods; K. Wrzosek-Lipska
• Department/s: Nuclear physics
• Publishing year: 2014
• Language: English
• Publication/Series: Physical Review C (Nuclear Physics)
• Volume: 89
• Issue: 2
• Links: http://dx.doi.org/10.1103/PhysRevC.89.024309
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 0556-2813