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arXiv · 1307.5502

Correlated two-neutron emission in the decay of unbound nucleus 26O

K. Hagino·H. Sagawa
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Abstract

The particle unbound $^{26}$O nucleus is located outside the neutron drip line, and spontaneously decays by emitting two neutrons with a relatively long life time due to the centrifugal barrier. We study the decay of this nucleus with a three-body model assuming an inert $^{24}$O core and two valence neutrons. We first point out the importance of the neutron-neutron final state interaction in the observed decay energy spectrum. We also show that the energy and and angular distributions for the two emitted neutrons manifest a clear evidence for the strong neutron-neutron correlation in the three-body resonance state. In particular, we find an enhancement of two-neutron emission in back-to-back directions. This is interpreted as a consequence of {\it dineutron correlation}, with which the two neutrons are spatially localized before the emission.

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K. Hagino, H. Sagawa. 2013-08-15. Correlated two-neutron emission in the decay of unbound nucleus 26O. https://doi.org/10.1103/physrevc.89.014331

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