The wobbling motion of a triaxial rotor coupled to a high-j quasiparticle is treated semiclassically. Longitudinal and transverse coupling regimes can be distinguished depending on, respectively, whether the quasiparticle angular momentum is oriented parallel or perpendicular to the rotor axis with the largest moment of inertia. Simple analytical expressions for the wobbling frequency and the electromagnetic E2 and M1 transition probabilites are derived assuming rigid alignment of the quasiparticle with one of the rotor axes and harmonic oscillations (HFA). Transverse wobbling is characterized by a decrease of the wobbling frequency with increasing angular momentum. Two examples for transverse wobbling, 163 Lu and 135 Pr, are studied in the framework of the full triaxial particle-rotor model and the HFA. The signature of transverse wobbling, decreasing wobbling frequency and enhanced E2 inter-band transitions, is found in agreement with experiment.

It is shown that the rotating mean field of triaxial nuclei can break the chiral symmetry. Two nearly degenerate DeltaI=1 rotational bands originate from the left-handed and right-handed solutions.

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Photoexcitation of the N = 50 nucleus 89 Y has been performed at the bremsstrahlung facility at the superconducting electron accelerator ELBE at electron energies of E kin e = 9.5 and 13.2 MeV. About 250 levels up to the neutron-separation energy were identified. Statistical methods were applied to estimate intensities of inelastic transitions and to correct the intensities of the ground-state transitions for their branching ratios. The photoabsorption cross section derived in this way up to the neutron-separation energy is combined with the photoabsorption cross section obtained from (γ, n) data and provides information about the extension of the giant dipole resonance toward energies below the neutron-separation energy. An enhancement of E1 strength has been found in the range from about 6 to 11 MeV. The experimental photoabsorption cross sections of 89 Y and of the neighboring N = 50 isotones 88 Sr and 90 Zr are compared with predictions of the quasiparticle-random-phase approximation.