Three-body model for the two-neutron decay of ${}^{16}$Be

Abstract

While diproton decay was first theorized in 1960 and first measured in 2002, it was first observed only in 2012. The measurement of ${}^{14}$Be in coincidence with two neutrons suggests that ${}^{16}$Be does decay through the simultaneous emission of two strongly correlated neutrons. In this work, we construct a full three-body model of ${}^{16}$Be (as ${}^{14}$Be + n + n) in order to investigate its configuration in the continuum and in particular the structure of its ground state. In order to describe the three-body system, effective n-${}^{14}$Be potentials were constructed, constrained by the experimental information on ${}^{15}$Be. The hyperspherical R-matrix method was used to solve the three-body scattering problem, and the resonance energy of ${}^{16}$Be was extracted from a phase shift analysis. In order to reproduce the experimental resonance energy of ${}^{16}$Be within this three-body model, a three-body interaction was needed. For extracting the width of the ground state of ${}^{16}$Be, we use the full width at half maximum of the derivative of the three-body phase shifts and the width of the three-body elastic scattering cross section. Our results confirm a dineutron structure for ${}^{16}$Be, dependent on the internal structure of the subsystem ${}^{15}$Be.

arXiv comment13 pages, 9 figures, submitted to Phys. Rev. C

References in corpus (11)

• An accurate nucleon-nucleon potential with charge-independence breaking
• First observation of 54Zn and its decay by two-proton emission
• FaCE: a tool for Three Body Faddeev calculations with core excitation
• Study of two-neutron radioactivity in the decay of 26O
• Correlated two-neutron emission in the decay of unbound nucleus 26O
• Lifetime and fragment correlations for the two-neutron decay of ${}^{26}$O ground state
• Comment on "First Observation of Ground State Dineutron Decay: 16Be"
• Two-Neutron Sequential Decay of ${}^{24}$O
• Effects of deformation in the three-body structure of 11Li
• Search for unbound 15Be states in the 3n+12Be channel
• Single-particle motion at large distances in 2N+core cluster systems near the drip line: a challenge for nuclear theory and experiment

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