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A soft mode in a finite Fermi-system: anharmonic effects near the instability point

Vladimir Zelevinsky·Alexander Volya
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Abstract

We consider a finite Fermi-system where the residual interactions create a soft mode of the excitation spectrum. Because of the large vibrational amplitude, the standard random phase approximation does not work in this situation. We develop a regular method for constructing the anharmonic potential and illustrate the application of the formalism by a simple model.

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Vladimir Zelevinsky, Alexander Volya. 2001-12-04. A soft mode in a finite Fermi-system: anharmonic effects near the instability point. https://arxiv.org/abs/nucl-th/0112013

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