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arXiv · 1203.2398

Breaking of N=8 magicity in 13Be

Yoshiko Kanada-En'yo
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Abstract

Structure of $^{13}$Be was investigated with antisymmetrized molecular dynamics. The variation after spin and parity projections was performed. An unnatural parity $1/2^-$ state was suggested to be lower than $5/2^+$ state indicating that vanishing of the N=8 magic number occurs in $^{13}$Be. A low-lying $3/2^+$ state with a $2\hbar\omega$ configuration was also suggested. Developed cluster structures were found in the intruder states. Lowering mechanism of the intruder states was discussed in terms of molecular orbitals around a $2\alpha$ core.

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Yoshiko Kanada-En'yo. 2012-03-12. Breaking of N=8 magicity in 13Be. https://doi.org/10.1103/physrevc.85.044320

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