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arXiv · 0907.4707

Elimination of $0^+$ spurious states in the quasiparticle time blocking approximation

V. I. Tselyaev
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Abstract

The quasiparticle time blocking approximation (QTBA) is considered as a model for the description of excitations in open-shell nuclei. The QTBA is an extension of the quasiparticle random phase approximation that includes quasiparticle-phonon coupling. In the present version of the QTBA, the pairing correlations are included within the framework of the BCS approximation. Thus, in this model, the $0^+$ spurious states appear, which are caused by the breaking of the symmetry related to the particle-number conservation. In this work, the method is described which solves the problem of the $0^+$ spurious states in the QTBA with the help of the projection technique. The method is illustrated by calculations of $0^+$ excitations in $^{120}$Sn nucleus.

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V. I. Tselyaev. 2009-07-27. Elimination of $0^+$ spurious states in the quasiparticle time blocking approximation. https://doi.org/10.3103/s1062873810060286

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