arXiv subjects

V. Vasilevsky

Publications and source records attributed to V. Vasilevsky.

7 recordsLinked to original sources

arXiv2010

JM-ECS: A hybrid method combining the $J$-matrix and ECS methods for scattering calculations

The paper proposes a hybrid method for calculating scattering processes that combines the $J$-matrix method with exterior complex scaling as an absorbing boundary condition. It represents the wave function as a finite sum of oscillator eigenstates in the inner region and on grid in the outer region. The method is validated for one and two dimensional model partial wave equation equations. Finally, the method calculates nuclear $p$-shell scattering.

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arXiv2004

On the Regularisation in J-matrix Methods

We investigate the effects of the regularization procedure used in the J-Matrix method. We show that it influences the convergence, and propose an alternative regularization approach. We explicitly perform some model calculations to demonstrate the improvement.

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arXiv2004

Monopole and quadrupole polarization effects on the alpha-particle description of $^{8}$Be

We investigate the effect of monopole and quadrupole modes on the elastic alpha-alpha resonance structure of $^{8}$Be. To this end we make a fully microscopic coupled channels calculation with three coupled channels, using the Algebraic Model. The continuum spectrum and wave functions are analyzed in terms of the individual channels to understand the nature of the resonances. It is shown that both monopole and quadrupole modes have a non-negligible effect on the resonances in the alpha-alpha continuum.

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arXiv2004

Theoretical analysis of resonance states in $^{4}H$, $^{4}He$ and $^{4}Li$ above three-cluster threshold

The resonance states of $^{4}H$, $^{4}He$ and $^{4}Li$, embedded in the three-cluster $d+N+N$ continuum, are investigated within a three-cluster model. The model treats the Pauli principle exactly and incorporates the Faddeev components for proper description of the boundary conditions for the two- and three-body continua. The hyperspherical harmonics are used to distinguish and numerate channels of the three-cluster continuum. It is shown that the effective barrier, created by three-cluster configuration $d+N+N$, is strong enough to accommodate two resonance states.

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arXiv2004

The Modified J-Matrix Approach for Cluster Descriptions of Light Nuclei

We present a fully microscopic three-cluster nuclear model for light nuclei on the basis of a J-Matrix approach. We apply the Modified J-Matrix method on $^{6}He$ and $^{6}Be$ for both scattering and reaction problems, analyse the Modified J-Matrix calculation, and compare the results to experimental data.

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arXiv2000

Algebraic Model for scattering in three-s-cluster systems. I. Theoretical Background

A framework to calculate two-particle matrix elements for fully antisymmetrized three-cluster configurations is presented. The theory is developed for a scattering situation described in terms of the Algebraic Model. This means that the nuclear many-particle state and its asymptotic behaviour are expanded in terms of oscillator states of the intra-cluster coordinates. The Generating Function technique is used to optimize the calculation of matrix elements. In order to derive the dynamical equations, a multichannel version of the Algebraic Model is presented.

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arXiv2000

Algebraic Model for scattering of three-s-cluster systems. II. Resonances in the three-cluster continuum of 6He and 6Be

The resonance states embedded in the three-cluster continuum of 6He and 6Be are obtained in the Algebraic Version of the Resonating Group Method. The model accounts for a correct treatment of the Pauli principle. It also provides the correct three-cluster continuum boundary conditions by using a Hyperspherical Harmonics basis. The model reproduces the observed resonances well and achieves good agreement with other models. A better understanding for the process of formation and decay of the resonance states in six-nucleon systems is obtained.

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