The deformation of Ne isotopes in the island-of-inversion region is determined by the doublefolding model with the Melbourne g-matrix and the density calculated by the antisymmetrized molecular dynamics (AMD). The double-folding model reproduces, with no adjustable parameter, the measured reaction cross sections for the scattering of 28−32 Ne from 12 C at 240MeV/nucleon. The quadrupole deformation thus determined is around 0.4 in the island-of-inversion region and 31 Ne is a halo nuclei with large deformation. We propose the Woods-Saxon model with a suitably chosen parameterization set and the deformation given by the AMD calculation as a convenient way of simulating the density calculated directly by the AMD. The deformed Woods-Saxon model provides the density with the proper asymptotic form. The pairing effect is investigated, and the importance of the angular momentum projection for obtaining the large deformation in the island-of-inversion region is pointed out.

We perform the first quantitative analysis of the reaction cross sections of 28−32 Ne by 12 C at 240 MeV/nucleon, using the double-folding model (DFM) with the Melbourne g-matrix and the deformed projectile density calculated by the antisymmetrized molecular dynamics (AMD). To describe the tail of the last neutron of 31 Ne, we adopt the resonating group method (RGM) combined with AMD. The theoretical prediction excellently reproduce the measured cross sections of 28−32 Ne with no adjustable parameters. The ground state properties of 31 Ne, i.e., strong deformation and a halo structure with spin-parity 3/2 − , are clarified.

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Isotope-dependence of measured reaction cross sections in scattering of 28−32 Ne isotopes from 12 C target at 240 MeV/nucleon is analyzed by the double-folding model with the Melbourne g-matrix. The density of projectile is calculated by the mean-field model with the deformed Wood-Saxon potential. The deformation is evaluated by the antisymmetrized molecular dynamics. The deformation of projectile enhances calculated reaction cross sections to the measured values.

The three moments of inertia associated with the wobbling mode built on the superdeformed states in 163 Lu are investigated by means of the cranked shell model plus random phase approximation to the configuration with an aligned quasiparticle. The result indicates that it is crucial to take into account the direct contribution to the moments of inertia from the aligned quasiparticle so as to realize J x > J y in positive-gamma shapes. Quenching of the pairing gap cooperates with the alignment effect. The peculiarity of the recently observed 163 Lu data is discussed by calculating not only the electromagnetic properties but also the excitation spectra.PACS numbers: 21.10. Re, 21.60.Jz, 23.20.Lv Rotation is one of the specific collective motions in finite many-body systems. Most of the nuclear rotational spectra can be understood as the outcome of one-dimensional (1D) rotations of axially symmetric nuclei. Two representative models -the moment of inertia of the irrotational fluid, J irr , and that of the rigid rotor, J rig , both specified by an appropriate axially-symmetric deformation parameter β -could not reproduce the experimental ones,From a microscopic viewpoint, the moment of inertia can be calculated as the response of the many-body system to an externally forced rotation -the cranking model [1]. This reproduces J exp well by taking into account the pairing correlation. Triaxial nuclei can rotate about their three principal axes and the corresponding three moments of inertia depend on their shapes in general. In spite of a lot of theoretical studies, their shape (in particular the triaxiality parameter γ) dependence has not been understood well because of the lack of decisive experimental data. Recently some evidences of three-dimensional (3D) rotations have been observed, such as the shears bands and the so-called chiral-twin bands [2]. In addition to these fully 3D motions, from the general argument of symmetry breaking, there must be a low-lying collective mode associated with the symmetry reduction from a 1D rotating axially symmetric mean field to a 3D rotating triaxial one. This is called the wobbling mode. Notice that the collective mode associated with the "phase transition" from an axially symmetric to a triaxial mean field in the nonrotating case is the well known gamma vibration. Therefore the wobbling mode can be said to be produced by an interplay of triaxiality and rotation. The wobbling mode is described as a small amplitude fluctuation of the rotational axis away from the principal axis with the largest moment of inertia. Bohr and Mottelson first discussed this mode [3].Mikhailov and Janssen [4] and Marshalek [5] described this mode in terms of the random phase approximation (RPA) in the rotating frame. In these works it was shown that at γ = 0 this mode turns into the odd-spin members of the gamma-vibrational band while at γ = 60 • or −120 • it becomes the precession mode built on top of the high-K isomeric states [6]. Here we note that, according to the direction of the rotational axis ...