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arXiv · 1804.03895

Two-Neutron Halo State of ${}^{15}$B Around $3.48$ MeV By A Three-Body Model

Dong Bai·Zhongzhou Ren·Tiekuang Dong
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Abstract

We investigate low-lying bound states of the neutron-rich nucleus ${}^{15}$B by assuming it is a three-body system made of an inert core ${}^{13}$B and two valence neutrons. The three-body wave functions are obtained using the Faddeev formalism. Special attention is paid to the excited state at $3.48(6)$ MeV observed in the ${}^{13}\text{C}({}^{14}\text{C},{}^{12}\text{N}){}^{15}\text{B}$ reaction, whose properties are less clear theoretically. In our three-body model, besides the ground state $3/2_1^-$, a second $3/2_2^-$ state is discovered at around $3.61$ MeV, which might be identified with the excited state observed at $3.48(6)$ MeV. We study this $3/2_2^-$ state in detail, which turns out to be a two-neutron halo state with a large matter radius $r_\text{m}\approx 4.770$ fm.

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Dong Bai, Zhongzhou Ren, Tiekuang Dong. 2018-04-11. Two-Neutron Halo State of ${}^{15}$B Around $3.48$ MeV By A Three-Body Model. https://doi.org/10.1088/1674-1137%2F42%2F6%2F064103

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