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Soft dipole mode in $^{11}$Li and three body continuum

Yu. A. Lurie·A. M. Shirokov·Yu. F. Smirnov
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Abstract

Properties of the neutron rich $^{11}$Li nucleus are calculated in the framework of the cluster model $^{9}$Li $+n+n$. The formalism of the harmonic oscillator representation of the scattering theory is used for the description of bound and continuum spectrum states in the three-body-democratic-decay approximation. It is shown that this approach allows one to take into account adequately the long asymptotic tail of the $^{11}$Li wave function ({\em neutron halo}) and to reproduce correctly the binding energy, radius and $^{11}$Li electromagnetic dissociation cross-section on target nuclei. The shape and the energy position of the $B(E1)$ peak corresponding to the soft dipole mode are also in agreement with experiment.

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Yu. A. Lurie, A. M. Shirokov, Yu. F. Smirnov. 1994-07-06. Soft dipole mode in $^{11}$Li and three body continuum. https://arxiv.org/abs/nucl-th/9407011

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