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arXiv · 1906.11418

Importance of multicranked configuration mixing for angular-momentum-projection calculations: Study of superdeformed rotational bands in $^{152}$Dy and $^{194}$Hg

Masaki Ushitani·Shingo Tagami·Yoshifumi R. Shimizu
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Abstract

Recently we have investigated an effective method of multicranked configuration-mixing for angular-momentum-projection calculation, where several cranked mean-field states are coupled after projection: The basic idea was originally proposed by Peierls and Thouless more than fifty years ago. With this method a good description of the rotational band has been achieved in a fully microscopic manner. In the present work, we apply the method to the high-spin superdeformed band, for which long rotational sequence is observed, and study how the good description is obtained for the rotational spectrum as well as the $\Jonem$ and $\Jtwom$ moments of inertia as functions of angular momentum. The Gogny D1S force is employed as an effective interaction, and the yrast superdeformed bands in $^{152}$Dy and $^{194}$Hg are taken as typical examples in the $A\approx 150$ and $A\approx 190$ regions, respectively. The effect of pairing correlations is examined by the variation after particle-number projection approach to understand the different behaviors of $\Jtwom$ moments of inertia observed in these two nuclei. The particle-number projection on top of the angular-momentum projection has been performed for the first time with the multicranked configuration-mixing.

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Masaki Ushitani, Shingo Tagami, Yoshifumi R. Shimizu. 2019-06-27. Importance of multicranked configuration mixing for angular-momentum-projection calculations: Study of superdeformed rotational bands in $^{152}$Dy and $^{194}$Hg. https://doi.org/10.1103/physrevc.99.064328

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