Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F,4n)134Pr. Recoil distance Doppler-shift and Doppler-shift attenuation measurements using the Euroball spectrometer, in conjunction with the inner Bismuth Germanate ball and the Cologne plunger, were performed at beam energies of 87 MeV and 83 MeV, respectively. Reduced transition probabilities in 134Pr are compared to the predictions of the two quasiparticle + triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in 134Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in 134Pr can be supported.

The available data on levels in 98 Y have been reevaluated and interpreted using recently published information on band structure in this region. A calculation in the interacting boson model framework suggests that the 1182 keV 0.8 s isomer is a spherical 10 − state with the g 9/2 h 11/2 configuration. This assignment implies that the 8.0 s bandhead at 496 keV is a I =4 − state, with the highly probable ͓422͔5/2 ͓541͔3/2 configuration. The level structure of 98 Y is well reproduced by coupling the levels of its both spherical and deformed odd-A neighbors and the origin of the isomeric states is understood.

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The chiral interpretation of twin bands in odd-odd nuclei was investigated in the interacting boson fermionfermion model. The analysis of the wave functions has shown that the possibility for angular momenta of the valence proton, neutron and core to find themselves in the favorable, almost orthogonal geometry is present, but not dominant. Such behavior is found to be similar in nuclei where both the level energies and the electromagnetic decay properties display the chiral pattern, as well as in those where only the level energies of the corresponding levels in the twin bands are close together. The difference in the structure of the two types of chiral candidates nuclei can be attributed to different β and γ fluctuations, induced by the exchange boson-fermion interaction of the interacting boson fermion-fermion model. In both cases the chirality is weak and dynamic.