Wobbling Motion in Triaxial Superdeformed NucleiMasayuki MatsuzakiFukuoka University of Educationbased on MM, Shimizu and Matsuyanagi, PR C65, 041303(R) and C69, 034325

Shell gap stable configurationsSuperdeformation2:1deformationsingle particle energy 2

Shell gaps in Nilsson diagram atneutron Suggest triaxial superdeformation (TSD) around proton

deformation in rotating systems

R.Bengtsson, http://www.matfys.lth.se/~ragnar/TSD-ensyst.htmlTSDTSDND-----+20------2022

TSD (>0) TSD(

rotTriaxial rotations about 3 axes are possible wobblingphonon

TSD1: 0 phonon (yrast)TSD2: 1 phononTSD3: 2 phononTSD4: another conf.

+20 contradicts irrotational ?

Rotating odd-mass nucleus can be regarded as rotor plus 1qp1qp also carries moment of inertiaThus, inertia of the whole system should be considered (in contrast to PRM)

Irrotational + QP align wobbling allowed

(If inertia are constant,)

Extremely collectiveas an RPA solutionbut

(dens)=20rather than (Nils)=20resolves discrepancy in B(E2) ratioParameterizations of triaxial deformation

TSD1: 0 phonon (yrast)TSD2: 1 phononTSD3: 2 phononTSD4: another conf.

2 phonon1 phononindicates softening of potential Removal of 1qp makes wobbling unstable

SummaryJx from QP alignment superimposed on irrot.-like inertia brings Jx > Jy for >0 --- This assures the existence of wobbling exc. Wobbling mode in 163Lu is naturally described semi-quantitatively in terms of RPAAnharmonicity of 2-phonon states suggests softening of potential surface

china_matsuzaki.ppt