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arXiv · 1608.05885

Shell Model States in the Continuum

A. M. Shirokov·A. I. Mazur·I. A. Mazur·J. P. Vary
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Abstract

We suggest a method for calculating scattering phase shifts and energies and widths of resonances which utilizes only eigenenergies obtained in variational calculations with oscillator basis and their dependence on oscillator basis spacing $\hbarΩ$. We make use of simple expressions for the $S$-matrix at eigenstates of a finite (truncated) Hamiltonian matrix in the oscillator basis obtained in the HORSE ($J$-matrix) formalism of quantum scattering theory. The validity of the suggested approach is verified in calculations with model Woods--Saxon potentials and applied to calculations of $nα$ resonances and non-resonant scattering using the no-core shell model.

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A. M. Shirokov, A. I. Mazur, I. A. Mazur, J. P. Vary. 2016-11-03. Shell Model States in the Continuum. https://doi.org/10.1103/physrevc.94.064320

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