Fragmentation of the Scissors Mode in Deformed Nuclei

J. P. Draayer, Louisiana State University
T. Beuschel, Louisiana State University
D. Rompf, Justus-Liebig-Universität Gießen
J. G. Hirsch, Centro de Investigacion y de Estudios Avanzados


A proton-neutron pseudo-SU(3) model is used to study the nature of low-lying magnetic dipole excitations. Triaxiality of the parent proton and neutron distributions is shown to add a "twist" degree of freedom to the usual scissors-mode picture and is reflected in a more complex spectrum of transition strengths for the magnetic dipole mode (M1). Fragmentation of the M1-strength distribution can be reproduced within the model by including single-particle terms and pairing in the Hamiltonian.