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arXiv · 1712.02006

Effects of ground-state correlations on dipole and quadrupole excitations of $^{40}$Ca and $^{48}$Ca

Mitsuru Tohyama
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Abstract

The effects of ground-state correlations on the dipole and quadrupole excitations are studied for $^{40}$Ca and $^{48}$Ca using the extended random phase approximation (ERPA) derived from the time-dependent density-matrix theory. Large effects of the ground-state correlations are found in the fragmentation of the giant quadrupole resonance in $^{40}$Ca and in the low-lying dipole strength in $^{48}$Ca. It is discussed that the former is due to a mixing of different configurations in the ground state and the latter is from the partial occupation of the neutron single-particle states. The dipole and quadrupole strength distributions below 10 MeV calculated in ERPA are in qualitatively agreement with experiment.

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Mitsuru Tohyama. 2017-12-06. Effects of ground-state correlations on dipole and quadrupole excitations of $^{40}$Ca and $^{48}$Ca. https://arxiv.org/abs/1712.02006

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