title: Spin and magnetic moment of 33Mg: evidence for a negative-parity intruder ground state.
abstract: We report on the first determination of the nuclear ground-state spin of 33Mg, I=3/2, and its magnetic moment, mu= -0.7456(5) mu(N), by combining laser spectroscopy with nuclear magnetic resonance techniques. These values are inconsistent with an earlier suggested 1 particle-1 hole configuration and provide evidence for a 2 particle-2 hole intruder ground state with negative parity. The results are in agreement with an odd-neutron occupation of the 3/2 [321] Nilsson orbital at a large prolate deformation. The discussion emphasizes the need of further theoretical and experimental investigation of the island of inversion, a region previously thought to be well understood.
authors.affiliation: Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium.
authors.forename: D T
authors.initials: DT
authors.lastname: Yordanov
authors.forename: M
authors.initials: M
authors.lastname: Kowalska
authors.forename: K
authors.initials: K
authors.lastname: Blaum
authors.forename: M
authors.initials: M
authors.lastname: De Rydt
authors.forename: K T
authors.initials: KT
authors.lastname: Flanagan
authors.forename: P
authors.initials: P
authors.lastname: Lievens
authors.forename: R
authors.initials: R
authors.lastname: Neugart
authors.forename: G
authors.initials: G
authors.lastname: Neyens
authors.forename: H H
authors.initials: HH
authors.lastname: Stroke