Yu. V. Palchikov

Effect of transport coefficients on the time dependence of a density matrix

For Lindblads master equation of open quantum systems with a general quadratic form of the Hamiltonian, the propagator of the density matrix is analytically calculated by using path integral techniques. The time-dependent density matrix is applied to nuclear barrier penetration in heavy ion collisions with inverted oscillator and double-well potentials. The quantum mechanical decoherence of pairs of phase space histories in the propagator is studied and shown that the decoherence depends crucially on the transport coefficients.For Lindblads master equation of open quantum systems with the Hamiltonian in a general quadratic form, the propagator of the density matrix is calculated analytically by using path-integral techniques. The time-dependent density matrix is applied to nuclear barrier penetration in heavy ion collisions with inverted oscillator and double-well potentials. The quantum mechanical decoherence of pairs of phase space histories in the propagator is studied and it is shown that the decoherence depends crucially on the transport coefficients.

Nuclear structure in the dinuclear model with rotating clusters

The dinuclear-system model can be applied to nuclear structure. Here, we study deformed clusters which rotate with respect to the internuclear distance and exchange nucleons. The model can be used to explain the band structure of nuclear spectra, especially the parity splitting observed in actinides, e.g., in 238U.

Nuclear structure with the dinuclear model

The dinuclear system concept is applied to the explanation of the structure of nuclei. The appearance of a low-lying band with negative parity states near the ground-state band in actinides and other nuclei is described by oscillations of the dinuclear system in the mass-asymmetry coordinate. The results for the parity splitting and electric multipole moments in alternating parity bands of these nuclei are in agreement with experimental data. The ground-state band and the superdeformed band of 60Zn are interpreted as being caused by α-particle and Be clusterizations, respectively. Hyperdeformed nuclei are assumed as dinuclear systems which could directly be built up in heavy-ion collisions. Signatures of hyperdeformed states in such reactions could be γ transitions between these states and their decay into the nuclei forming the hyperdeformed nucleus.

Superdeformation as cluster state

A cluster approach is applied to describing the decay-out phenomenon of the yrast superdeformed states for mass region A≈190.

Relation between E2-transition probabilities for nuclei that are soft with respect to β vibrations

AbstractFor collective even-even nuclei, a relation between the E2-transition probabilities, which characterize the decay properties of

Fission transient time with quantum master equation

0_{2^ - }^ +

Non-Markovian dynamics of quantum systems. II. Decay rate, capture, and pure states.

and 2γ+ states, are obtained. This relation features no free parameters; it is applicable to describing nuclei that are soft with respect to β vibrations. The 152Sm and 154Gd nuclei are considered as examples illustrating the application of the aforementioned relation.

Universal description of the02+state in collective even-Anuclei

SummaryThe relationship between the cluster properties of heavy nuclei and the appearance of low-lying collective negative-parity states in these nuclei is discussed. Energies of the cluster typenp-nh particle-hole excited states, wheren is the number of nucleons in a cluster, are calculated. It is shown that the energies of these states take minimal values in nuclei having low-lying collective 1- states and ground-state alternating-parity rotational bands with ΔI = 1. The correlation between the difference of the quadrupole deformations in the potential energy minimum and at the barrier separating two octupole minima and the value of the angular momentum, at which parity splitting disappears, is studied.