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arXiv · 1509.01193

Two neutron decay of 16Be

A. E. Lovell·F. M. Nunes·I. J. Thompson
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Abstract

Recently, the first example of two-neutron decay from the ground state of an unbound nucleus, $^{16}$Be, was seen. Three-body methods are ideal for exactly treating the degrees of freedom important for these decays. Using a basis expansion over hyperspherical harmonics and the hyperspherical R-matrix method, we construct a realistic model of $^{16}$Be in order to investigate its decay mode and the role of the two-neutron interaction. The neutron-$^{14}$Be interaction is constrained using shell model predictions. We obtain a ground state for $^{16}$Be that is over-bound by approximately 1 MeV with a width of approximately 0.23 MeV. This suggests, that for such systems, the three-body force needs to be repulsive.

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A. E. Lovell, F. M. Nunes, I. J. Thompson. 2015-09-03. Two neutron decay of 16Be. https://doi.org/10.1051/epjconf%2F201611306015

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