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arXiv:2009.02014

Effects of ground-state correlations on magnetic dipole excitations in $^{40}$Ca

M. Tohyama

Published Sep 4, 2020• 0 citations
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Abstract

The effects of ground-state correlations on the magnetic dipole excitations in $^{40}$Ca are studied using an extended random phase approximation (ERPA) derived from the time-dependent density-matrix theory. Comparison is made with other extended RPA approaches, the renormalized RPA, the self-consistent RPA and the extended second RPA which also include the effects of ground-state correlations. It is pointed out that direct excitations from two particle - two hole space which are properly treated in ERPA cause strong magnetic dipole transitions in $^{40}$Ca.

DOI
10.48550/arxiv.2009.02014

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Effects of ground-state correlations on magnetic dipole excitations in 40^{40}40Ca
The effects of ground-state correlations on the magnetic dipole excitations in 40^{40}40Ca are studied using an extended random phase approximation (ERPA) derived from the time-dependent density-matrix theory. Comparison is made with other extended RPA approaches, the renormalized RPA, the self-consistent RPA and the extended second RPA which also include the effects of ground-state correlations. It is pointed out that direct excitations from two particle - two hole space which are properly treated in ERPA cause strong magnetic dipole transitions in 40^{40}40Ca.
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