29Na: Defining the Edge of the Island of Inversion for Z=11

Journal Article · Mon Apr 25 00:00:00 EDT 2005 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.94.162501· OSTI ID:918918

Tripathi, V; Tabor, S L; Mantica, P F; Hoffman, C R; Wiedeking, M; Davies, A D; Liddick, S N; Mueller, W F; Otsuka, T; Stolz, A; Tomlin, B E; Utsuno, Y; Volya, A

The low-energy level structure of the exotic Na isotopes {sup 28,29}Na has been investigated through beta-delayed gamma spectroscopy. The N=20 isotones for Z=10-12 are considered to belong to the 'island of inversion' where intruder configurations dominate the ground state wave function. However, it is an open question as to where and how the transition from normal to intruder dominated configurations happens in an isotopic chain. The present work, which presents the first detailed spectroscopy of {sup 28,29}Na, clearly demonstrates that such a transition in the Na isotopes occurs between {sup 28}Na (N=17) and {sup 29}Na (N=18), supporting the smaller N=20 shell gap in neutron-rich sd shell nuclei. The evidence for inverted shell structure is found in beta-decay branching ratios, intruder dominated spectroscopy of low-lying states, and shell model analysis.

• Research Organization: COLLABORATION - Florida StateU.
• Sponsoring Organization: USDOE Director. Office of Science. NuclearPhysics
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 918918
• Report Number(s): LBNL-61506; PRLTAO; R&D Project: NUCST; BnR: KB0401024; TRN: US0805922
• Journal Information: Physical Review Letters, Vol. 94; Related Information: Journal Publication Date: 04/29/2005; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

73
BETA DECAY
BRANCHING RATIO
GAMMA SPECTROSCOPY
GROUND STATES
ISLANDS
ISOTONIC NUCLEI
NUCLEI
SHELL MODELS
SPECTROSCOPY
WAVE FUNCTIONS
SODIUM 29