Mr
Hiroshi Oba
(Graduate School of Science and Technology, Niigata University)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
The coordinate-space Hartree-Fock-Bogoliubov (HFB) method plus the continuum quasi-particle random phase approximation (QRPA)[1] is useful schemes to describe nuclei close to the neutron drip line as the methods allows us to treat properly the asymptotic behaviours of quasi-particle wave functions of weakly bound and unbound orbits. However, no complete formulation has been given once nuclear...
Dr
Makoto Ito
(RIKEN Nishina Center Accelerator based Science, RIKEN)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
The breaking of N=8 magic number in 12Be is suggested by recent experimental observations (anormalous deformation length, and low-lying 1- and excited 0+ and so on). In the present report, we will discuss the low-lying states of this nucleius based on the microscopic cluster model of alpha+alpha+4N. We will investigate the breaking of N=8 magic number from the viewpoints of the covalent...
Mr
Koshiroh Tsukiyama
(Department of physics, The University of Tokyo)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
Recently, neutron unbound low-lying states in oxygen isotopes near the drip line have been measured in several experiments. The conventional nuclear shell-model calculation, one of the most reliable methods in this mass region, cannot sufficiently explain the results. We therefore investigate the continuum effects, which have not been considered directly in the conventional shell model, for...
Mr
Nguyen Quang Hung
(Heavy Ion Nuclear Physics Laboratory, RIKEN Nishina Center)
03/04/2008, 17:40
Exotic deformation / new collective motion at low and high spin
Poster
The effects of angular momentum on pairing in nuclei are studied within the so-called FTBCS1 theory, which is an extension of the finite-temperature BCS theory including the thermal fluctuations such as quasiparticle-number fluctuations (QNF). For simplicity, the angular momentum projection M is introduced instead of the total one. The numerical calculations are carried out within a doubly...
Dr
Yasuo Wakabayashi
(Center for Nuclear Study, University of Tokyo)
03/04/2008, 17:40
Other
Poster
High spin isomers are known in N=83 isotones systematically.
These isomers are considered to be shape isomers caused
by sudden shape changes from near spherical to oblate shapes.
In order to search for high-spin isomers in other mass region,
the 90Zr region was selected.
Comparing the spherical single particle orbits near Fermi surfaces of nuclei
in these two regions, there are...
Dr
Koji Higashiyama
(Chiba Institute of Technology)
03/04/2008, 17:40
Exotic deformation / new collective motion at low and high spin
Poster
The band structure of the Se and Ge isotopes around the mass 80 is
studied in terms of the full-fledged shell model. The monopole and
quadrupole pairing plus quadrupole-quadrupole interaction is
employed as an effective interaction. As for single-particle levels, all
the four orbitals in the major shell between the magic numbers 28
and 50 are taken into account for both neutrons and...
Dr
Hiroshi Watanabe
(RIKEN)
03/04/2008, 17:40
Single particle motion in isomeric states
Poster
Isomeric states in atomic nuclei are unique probes which reveal various aspects of the microscopic structure of the nucleus and the nature of nuclear interactions. This presentation will focus on characteristic isomers in stable and neutron-rich odd-A antimony and iodine isotopes. The nuclei of interest were investigated by means of time-correlated gamma-ray spectroscopy with the GAMMASPHERE...
Mr
Daisuke Suzuki
(Department of Physics, University of Tokyo)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
Lifetime measurements have been performed for excited states in the neutron-rich carbon isotope 17C. Recently, several experimental studies have been dedicated to investigate the low-lying structure of 17C, revealing a couple of unique features inherent in the weakly-bound states located below the extremely low neutron emission threshold at 730 keV. The spin-parity of the ground state was...
Mr
Kosuke Nomura
(University of Tokyo)
03/04/2008, 17:40
Exotic deformation / new collective motion at low and high spin
Poster
Recently, various exotic nuclei with intriguing collectivities have been created, which motivate us to investigate the properties of neutron-rich A$\geq$200 region nuclei far from the stability line. We study the low-lying collective states, especially the quadrupole deformations, of these heavy unstable nuclei within the interacting boson model (IBM). A conventional way for the derivation of...
Dr
Kenichi Yoshida
(Department of Physics, Kyoto University and Institut de Physique Nucleaire, Universite Paris Sud)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
Microscopic structure of the low-lying isovector dipole excitation mode
in neutron-rich $^{26,28,30}$Ne is investigated by performing
deformed quasiparticle-random-phase-approximation (QRPA) calculations.
The particle-hole residual interaction is derived from a Skyrme force
through a Landau-Migdal approximation.
We have obtained the low-lying resonance in $^{26}$Ne at around 8.5...
Prof.
Naohito Iwasa
(Department of Physics, Tohoku University)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
The Coulomb excitation of the very proton-rich nucleus $^{20}$Mg was studied using a radioactive $^{20}$Mg beam at 58 $A$ MeV impinging on a lead target.
The reduced transition probability $B$(E2; $0^+_{gs}\rightarrow 2^+_1$) was extracted.
The ratio of the neutron-to-proton multipole matrix elements $M_n/M_p$
was deduced by comparing the $B$(E2) with that for the mirror nucleus...
Mr
Shuichiro Ebata
(Institute for Physics, Univ. of Tsukuba)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
We present a theoretical study of nuclear response using a method that
is applicable to systems from light to heavy nuclei systematically;
The real-time calculation of the time-dependent Hartree-Fock+BCS(TDHF+BCS)
in the 3-dimensional mesh representation.
The method is a simple extension of the well-known TDHF method but
is able to describe various responses of deformed nuclei with...
Dr
Tsunenori Inakura
(Univ. fo Tsukuba)
03/04/2008, 17:40
Collectivities and shell effects in neutron/proton-rich nuclei
Poster
Radioactive isotope facilities of the new generation enable
us to access unexplored territories of unstable nuclei with
large neutron excess. Theoretical studies and predictions
of properties of unknown nuclei are important subjects in
nuclear structure physics. In order to clarify peculiarities
of these exotic nuclei, we need systematic calculations
across the entire nuclear chart. The...
