Publication at Faculty of Mathematics and Physics |
2014
Abstract
The effect of nuclear deformation on the isoscalar toroidal and compression dipole modes in prolate Yb-170 is studied in the framework of the random-phase-approximation method with a representative set of Skyrme forces (SV-bas, SLy6, SkM* and SkI3). It is shown that the deformation crucially redistributes the strength of both modes.
The compression mode has the same sequence of mu = 0 and 1 branches as the isovector giant dipole resonance where for prolate nuclei the mu = 0 mode is lower in energy (mu being the projection of the axial momentum of the mode). Instead, the toroidal mode exhibits an unexpected (opposite) sequence where the mu = 1 branch precedes the mu = 0 one.