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Isolated States

A. M. Shirokov·Yu. F. Smirnov·S. A. Zaytsev
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Abstract

We show that a quantum system with nonlocal interaction can have bound states of unusual type (isolated states (IS)). IS is a bound state that do not generate a $S$-matrix pole. IS can have positive as well as negative energy and can be treated as a generalization of bound states embedded in continuum on the case of discrete spectrum states. Formation of IS in the spectrum of quantum system is studied using a simple rank--2 separable potential with harmonic oscillator formfactors. Some physical applications are discussed, in particular, we propose separable $NN$ potential that describes not only most important two-nucleon data (deuteron binding energy and s-wave triplet and singlet scattering phases) but also the trinucleon binding energy without making use of three-body forces.

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A. M. Shirokov, Yu. F. Smirnov, S. A. Zaytsev. 1994-06-30. Isolated States. https://arxiv.org/abs/nucl-th/9406036

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