| 1. |
- Fujita, Y, et al.
(författare)
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Evidence for the existence of the [202]3/2 deformed band in mirror nuclei Mg-25 and Al-25
- 2004
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Ingår i: Physical Review Letters. - 1079-7114. ; 92:6
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Tidskriftsartikel (refereegranskat)abstract
- After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5 MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0degrees having a strong selectivity for Gamow-Teller transitions. In the comparison with the analogous M1 transitions in Mg-25, the J(pi)=3/2(+) bandhead state and the excited 5/2(+) and 7/2(+) members were clearly assigned.
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| 2. |
- Fujita, Y., et al.
(författare)
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Identification of the [202]3/2 deformed band in mirror nuclei Mg-25 and Al-25 and implications for unstable nuclei
- 2006
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Ingår i: Physica Scripta. - 0031-8949. ; T125, s. 194-195
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Tidskriftsartikel (refereegranskat)abstract
- Fifty years after its prediction, the highest-lying [ 2 0 2] 3) 2 orbit among the six Nilsson single-particle orbits originating from the sd shell in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0 degrees having a strong selectivity for Gamow-Teller transitions. In comparison with the analogous M1 transitions in Mg-25, the J(pi) = 3/+ band-head state and the excited 5/+ and 7/2+ members were clearly assigned.
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| 3. |
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| 4. |
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| 5. |
- Hamamoto-Kuroda, Ikuko
(författare)
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Change of shell structure and magnetic moments of odd-N deformed nuclei towards the neutron drip line
- 2010
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 37:5
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Tidskriftsartikel (refereegranskat)abstract
- Examples of the change of neutron shell structure in both weakly bound and resonant neutron one-particle levels in nuclei towards the neutron drip line are exhibited. It is shown that the shell-structure change due to the weak binding may lead to the deformation of those nuclei with the neutron numbers N approximate to 8, 20, 28 and 40, which are known to be magic numbers in stable nuclei. Nuclei in the 'island of inversion' are most easily and in a simple manner understood in terms of deformation. As an example of spectroscopic properties other than single-particle energies, magnetic moments of some weakly bound possibly deformed odd-N nuclei with neutron numbers close to those traditional magic numbers are given, which are calculated using the wavefunction of the last odd particle in deformed Woods-Saxon potentials.
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| 6. |
- Hamamoto-Kuroda, Ikuko
(författare)
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Dominance of low-l component in weakly bound deformed single-neutron orbits
- 2004
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 69:4
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Tidskriftsartikel (refereegranskat)abstract
- Calculating single-particle (Nilsson) levels in axially symmetric quadrupole-deformed potentials in coordinate space, the structure of weakly bound neutron orbits is studied in the absence of pair correlation. It is shown that in the wave functions of Omega(pi)=1/2(+) orbits, where Omega expresses the projection of the particle angular momentum along the symmetry axis, the l=0 (s(1/2)) component becomes overwhelmingly dominant as the binding energy of the orbits approaches zero, irrespective of the size of the deformation and the kind of Nilsson orbits. Consequently, all Omega(pi)=1/2(+) levels become practically unavailable for both deformation and many-body pair correlation, when the levels approach continuum or lie in the continuum.
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| 7. |
- Hamamoto-Kuroda, Ikuko
(författare)
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Effect of weakly-bound neutrons on pair-correlation and deformation
- 2005
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Ingår i: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. ; 764, s. 157-163
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Konferensbidrag (refereegranskat)abstract
- The unique role of weakly-bound low-angular-momentum neutrons in the structure of neutron-drip-line nuclei is presented, studying both the many-body pair-correlation in spherical nuclei and the one-particle orbits in the deformed Woods-Saxon potential. Both the HFB equations in the former case and the Schrodinger equation in the latter are solved in coordinate space with correct asymptotic boundary conditions. Combining the results of those two cases, it is concluded, for example, that all Ωx=1/2+ one-particle levels become practically unavailable for both deformation and many-body pair-correlation, when the HF one-particle levels approach continuum or lie in the continuum
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| 8. |
- Hamamoto-Kuroda, Ikuko
(författare)
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Effective pair-gap of weakly-bound neutrons in deformed nuclei
- 2005
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 71:3
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Tidskriftsartikel (refereegranskat)abstract
- The dependence of effective pair gap on weakly bound neutron orbits is studied in deformed nuclei in comparison with that in spherical nuclei, solving the Hartree-Fock-Bogoliubov equation in a simplified model in coordinate space with the correct asymptotic boundary conditions. In spherical nuclei the effective pair gap of s1/2 neutrons decreases to zero in the limit that the corresponding Hartree-Fock one-particle energy approaches zero. In the same limit, the effective pair gap of =1/2+ neutrons in deformed nuclei becomes very small when the wave functions of =1/2+ orbits contain an appreciable amount of s1/2 components, even if a considerable amount of larger-components remains in the wave functions. Then, the one-particle excitation spectra of deformed even-even neutron-drip-line nuclei, in which an =1/2+ level is weakly bound, can start at much lower energy than twice the average pair gap in the presence of many-body pair correlation.
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| 9. |
- Hamamoto-Kuroda, Ikuko
(författare)
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Examining possible neutron-halo nuclei heavier than Mg 37
- 2017
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Ingår i: Physical Review C: covering nuclear physics. - 2469-9985. ; 95:4
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Tidskriftsartikel (refereegranskat)abstract
- The even-Z odd-N neutron-halo nuclei, which are the lightest neutron-halo nuclei heavier than Mg37, are explored by studying the shell structure unique in weakly bound neutrons for spherical or deformed shapes. It is pointed out that due to the narrowed N=50 spherical energy gap and a few resulting close-lying neutron one-particle levels, 1g9/2, 3s1/2, and 2d5/2, for spherical shape, nuclei with some weakly bound neutrons filling in those levels may be deformed and have a good chance to show deformed s-wave halos. Promising candidates are Cr472471, Cr492473, Cr512475, and Fe512677 in the case that those nuclei lie inside the neutron drip line. An interesting possibility of the deformed p-wave or s-wave halos is suggested also for the nucleus Ar351853.
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| 10. |
- Hamamoto-Kuroda, Ikuko, et al.
(författare)
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Further examination of prolate-shape dominance in nuclear deformation
- 2009
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 79:3
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Tidskriftsartikel (refereegranskat)abstract
- The observed almost complete dominance of prolate over oblate deformations in the ground states of deformed even-even nuclei is related to the splitting of high center dot "surface" orbits in the Nilsson diagram: on the oblate side the occurrence of numerous strongly avoided crossings which reduce the fanning out of the low Lambda orbits, while on the prolate side the same interactions increase the fanning out. It is further demonstrated that the prolate dominance is rather special for the restricted particle number of available nuclei and is not generic for finite systems with mean-field potentials resembling those in atomic nuclei.
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