Collective excitations in deformed nuclei

Nuclear scissors with pairing and continuity equation

“…The situation is completely different when pairing is included. In this case, the main contribution to the scissors mode energy comes from the pairing interaction, E sc is not proportional to δ, and the deformation dependence of B(M1) sc becomes quadratic in excellent agreement with QRPA calculations and experimental data [2,12,13,14,15,16,17,18].…”

“…Substituting this into (12) and changing the variables p ↔ p ′ , we obtain immediately the desired result. Examples for this type of calculation can be found in Appendix A.…”

“…x and ω τ z are written out in appendix B. For the sake of simplicity, we will neglect in (12) all terms proportional to h2 (quantum corrections) except the simplest one, namely the term with h 1 + , which we will keep in order to have an idea about the possible influence of quantum corrections. We assume that ∆ 0 does not depend on the direction of p, i.e.…”

Negative R-parity scissors modes in the Two-Rotors Model

“…It was devised as a model for deformed atomic nuclei, in which case the rigid bodies represent the proton and neutron systems [1]. The collective 1 + state, the scissors mode, predicted by this model was firstly observed [2] in 154 Gd and then in all deformed atomic nuclei [3]. Recently also the prediction [1] of the J = 2 member of its rotational band has been confirmed [4].…”

“…There is by now an extensive literature on the subject [3]: in all these papers the rotors were assumed to have axial symmetry and to be invariant under inversion of their axes. Their wf should therefore be even or odd under such an inversion, but only even states were considered.…”