Title: Wobbling Motion in Triaxial Superdeformed Nuclei
1Wobbling Motion in Triaxial Superdeformed Nuclei
Masayuki Matsuzaki
Fukuoka University of Education
based on MM, Shimizu and Matsuyanagi, PR C65,
041303(R) and C69, 034325
2Shell gap ? stable configurations
Superdeformation
single particle energy
21
2
deformation
3Shell gaps in Nilsson diagram at
neutron
proton
? Suggest triaxial superdeformation (TSD) around
4 ? deformation in rotating systems
5-----?20?
TSD
ND
2
-----?-20?
TSD
2
R.Bengtsson, http//www.matfys.lth.se/ragnar/TSD-
ensyst.html
6TSD (?gt0) TSD(?lt0) ND
R.Bengtsson, http//www.matfys.lth.se/ragnar/TSD-
ensyst.html
7Triaxial ? rotations about 3 axes are possible ?
wobbling
phonon
rot
8TSD1 0 phonon (yrast)
TSD2 1 phonon
TSD3 2 phonon
TSD4 another conf.
9?20? contradicts irrotational ?
10- Rotating odd-mass nucleus can be regarded as
rotor plus 1qp - 1qp also carries moment of inertia
- Thus, inertia of the whole system should be
considered (in contrast to PRM)
11(No Transcript)
12Irrotational QP align ? ?
wobbling allowed
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14(If inertia are constant,
)
15Extremely collective as an RPA solution but
16Parameterizations of triaxial deformation
?(dens)20rather than ?(Nils)20 resolves
discrepancy in B(E2) ratio
17TSD1 0 phonon (yrast)
TSD2 1 phonon
TSD3 2 phonon
TSD4 another conf.
182 phonon
1 phonon
indicates softening of potential
? Removal of 1qp makes wobbling unstable
19Summary
- ?Jx from QP alignment superimposed on irrot.-like
inertia brings Jx gt Jy for ?gt0 --- This assures
the existence of wobbling exc. - Wobbling mode in 163Lu is naturally described
semi-quantitatively in terms of RPA - Anharmonicity of 2-phonon states suggests
softening of potential surface