V. O. Nesterenko

Joint Institute for Nuclear Research | jinr ОИЯИ · Bogoliubov Laboratory of Theoretical Physics

The orbital M1 collective mode predicted for deformed clusters in a schematic model is studied in a self-consistent random-phase-approximation approach which fully exploits the shell structure of the clusters. The microscopic mechanism of the excitation is clarified and the close correlation with E2 mode established. The study shows that the M1 str...

A strength function method is adopted to describe a coupling between electric and magnetic modes of different multipolarity. The collective vibrations are analysed for a separable residual interaction in the framework of the random-phase approximation. The coupling between $M2$ and $E1$ giant resonances is considered as an illustrative example. Com...

The region of collective octupole states below the excitation energy of 7-8 MeV is studied for deformed nuclei in the random phase approximation (RPA). The calculational results show that the low-energy octupole resonances (LEOR) observed in nuclei from 90Zr to 154Sm in the reactions ( alpha , alpha ') should exist in well-deformed rare-earth and a...

The systematics of the plasmon response in spherical K, Na and Li clusters in a wide size region is studied. Two simplifying approximations whose validity has been established previously are considered: (a) a separable approach to the random-phase-approximation, involving an expansion of the residual interaction into a sum of separable terms, (b) t...

A strength function technique valid for a separable Hamiltonian which allows for the coupling between electric and magnetic channels is developed in the framework of proton-neutron random-phase approximation and applied to deformed nuclei. The signature formalism is adopted in view of future applications of the method to fast rotating nuclei. For i...

The self-consistent RPA (SRPA) withseparable residual interaction is applied to the description of Eλ giant resonances (multipole collective oscillations of valence electrons) in nuclei (metal clusters) of different shape. The method drastically simplifies RPA calculations, providing nevertheless reasonable agreement with available experimental dat...

The results of an investigation of the formation of Pb, Th, and U clusters over a broad range of numbers of atoms (from a few atoms to macroparticles) upon interaction of high-power pulsed laser radiation with matter are presented. Clusters of fissionable elements are studied for the first time. A setup for determining the yield of clusters and the...

The modified random-phase-approximation (RPA) method with the self-consistent separable residual forces (SRPA) is proposed for the description of multipole electric oscillations of valence electrons in sodium clusters. The method allows one to study the coupling of different kinds of collective motion. As a particular case, the coupling of surface...

The self-consistent RPA method (SRPA) with separable residual interaction is proposed for the description of collective oscillations of valence electrons in metal clusters (MC) of different shape. Being widely used in nuclear theory, the separable ansatz has not been accepted in recent time for MC. At the same time, this ansatz drastically simplifi...

The vibrating potential model, which represents a self-consistent version of the random-phase approximation (RPA) with a separable residual interaction, is generalized to the description of Elambda collective excitations in nuclei with any even-multipole static deformation. The model is used to study the isoscalar E2 and E3 giant resonances in defo...

The particle number projecting method for the description of pairing effects in metal clusters is proposed. In contrast with the Bardeen-Cooper-Schrieffer method (BCS) which does not conserve the particle number (thus not providing the necessary accuracy of calculations for small clusters) and has no solutions at sufficiently weak pairing, the proj...

The self-consistent vibrating potential model (VPM) is extended for the description ofEλ surface collective excitations in alkali metal clusters with practically any kind of static deformation. The case of spherical clusters is also covered. Any single-particle potentials and valence electron densities for which the coefficients of the multipole ex...

The microscopic approach for the description of low-lying intrinsic states in deformed odd-odd nuclei is formulated as a generalization of the quasiparticle-phonon model. In comparison with other models used for deformed odd-odd nuclei, the approach proposed in this paper involves vibrational degrees of freedom of the doubly-even core, their coupli...

A microscopic approach in the description of low-lying states in deformed odd-odd nuclei is formulated as a generalization of the quasiparticle-phonon model (QPM) including the rotational degrees of freedom and the n-p interaction between external nucleons. In comparison with other models, the approach proposed includes all the three most important...

The equations for the description of vibrational states in deformed odd-A nuclei are obtained within the quasiparticle-phonon nuclear model. In these equations the Pauli principle is taken into account in the quasiparticle plus phonon components of the wave functions. It is shown that if in these components the Pauli principle is not violated or is...

The strength functions b(E3, omega) are calculated, and the positions and widths of giant octupole resonances in deformed nuclei are found. It is shown that the giant octupole isoscalar resonances have energies (19-20) MeV for the rare-earth nuclei and (17-18) MeV for the actinides and the widths (5-7) MeV. The energies of the giant octupole isovec...

The non-relativistic energy magnitudes for the ground state of He and He isoelec- tronic series with atomic number Z =3 ÷ 54, are calculated. Calculations are performed using an explicitly correlated trial wave-functions of the generalized Hylleraas type. We have developed a variational procedure that allows solving the two-particle Schroedinger eq...

Despite a great success of the time-dependent Skyrme Hartree-Fock (TDSHF) approach in exploration of nuclear dynamics, it is still poorly applied to magnetic excitations, in particular to spin-flip M1 and scissors M1 giant resonances (GR). At the same time the spin-flip M1 GR can be an important source of knowledge on spin correlations in the Skyrm...

Calculations of giant quadrupole isoscalar and isovector resonances in the random-phase approximation are presented. The strength functions for E2 transitions are calculated for even-even deformed nuclei in the regions of 150< or =A

An analysis is reported of the effect of quasiparticle plus two phonon components on the energy and structure of states of odd nuclei. It is shown that for states with excitation energies below 0.7 to 1.0 MeV, these components can be neglected for highly deformed nuclei. Phonons with lambda greater than 3 can be ignored in calculations of the param...