A. P. Severyukhin

Effects of phonon-phonon coupling on low-lying states in neutron-rich Sn isotopes

Abstract.Starting from an effective Skyrme interaction we present a method to take into account the coupling between one- and two-phonon terms in the wave functions of excited states. The approach is a development of a finite rank separable approximation for the quasiparticle RPA calculations proposed in our previous work. The influence of the phonon-phonon coupling on energies and transition probabilities for the low-lying quadrupole and octupole states in the neutron-rich Sn isotopes is studied.

Separable Skyrme Interactions and Quasiparticle RPA

A finite rank separable approximation for the quasiparticle random phase approximation with Skyrme interactions is applied to study the low-lying quadrupole and octupole states in some S isotopes and giant resonances in some spherical nuclei. It is shown that characteristics calculated within the suggested approach are in good agreement with available experimental data.

Description of proton-neutron mixed-symmetry states with Skyrme interaction

Starting from an effective Skyrme interaction we study the effects of the phonon-phonon coupling on the M1 transitions between quadrupole states. The finite rank separable approach for the quasiparticle random phase approximation is used. Choosing as an example the nucleus 94Mo, we demonstrate an ability of the method to describe the properties of the low-lying states.

Nuclear structure calculations with a separable approximation for Skyrme interactions

Abstract A finite rank separable approximation for the quasiparticle RPA calculations with Skyrme interactions that was proposed in our previous work is extended to take into account the coupling between one- and two-phonon terms in the wave functions of excited states. It is shown that characteristics calculated within the suggested approach are in a good agreement with available experimental data.

Describing of the properties of quadrupole states in a 94Mo nucleus with skyrme interaction

The influence of coupling between simple and complex configurations on the probabilities of E2 and M1 transitions between vibrational quadrupole states is investigated. The finite rank separable approximation for the Skyrme effective forces is used. Properties of the low-energy spectrum for quadrupole excitations in 94Mo nucleus are considered.

Structure of low-lying quadrupole states in nucleus 134Xe

Starting from the Skyrme interaction, we study the M1 transitions between vibration quadrupole states. The finite rank separable approach for quasiparticle random phase approximation is used. As an example, we investigate the properties of the low-energy spectrum of quadrupole excitations in nucleus 134Xe.

Pair correlations and the time-dependent Hartree-Fock-Bogoliubov method in the theory of nuclear structure

It is shown that an idea of the superfluidity of nuclear matter and the u-v transformation of Bogoliubov, time-dependent Hartree-Fock-Bogoliubov method have made a strong impact on the development of the modern nuclear theory. Some applications of the Bogoliubov methods to describe properties of the low-lying collective nuclear states and the giant resonances are demonstrated.

Properties of giant dipole resonance and the elimination of center-of-mass motion

The accuracy of eliminating the spurious state from the E1-transition strength distribution is investigated within the random-phase approximation with separabelized Skyrme forces. The E1-transition strength distribution in 132Sn is considered as an example.

On the Qn ? Qp deformation energy surfaces of neutron-rich oxygen isotopes

We present an analysis based on the generator coordinate method that allows one to disentangle the neutron and proton contributions to the properties of low-lying collective states in oxygen isotopes.

Large-amplitude Qn-Qp collectivity in the neutron-rich oxygen isotope 20O

By means of HFB calculations with independent constraints on axial neutron and proton quadrupole moments Q^n and Q^p, we investigate the large amplitude isoscalar and isovector deformation properties of the neutron-rich isotope O20. Using the particle-number and angular-momentum projected generator coordinate method, we analyze the collective dynamics in the Q, Q plane. The parametrization SLy4 of the Skyrme interaction is used for all calculations in connection with a density-dependent zero-range pairing interaction. Our results show that already for this moderately neutron-rich nucleus the transition moments are modified when independent neutron and proton collective dynamics are allowed.