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arXiv · 1404.3019

Role of diproton correlation in two-proton emission decay of the $^6$Be nucleus

Tomohiro Oishi·Kouichi Hagino·Hiroyuki Sagawa
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Abstract

We discuss a role of diproton correlation in two-proton emission from the ground state of a proton-rich nucleus, $^6$Be. Assuming the three-body structure of $α+ p + p$ configuration, we develop a time-dependent approach, in which the two-proton emission is described as a time-evolution of a three-body metastable state. With this method, the dynamics of the two-proton emission can be intuitively discussed by monitoring the time-dependence of the two-particle density distribution. With a model Hamiltonian which well reproduces the experimental two-proton decay width, we show that a strongly correlated diproton emission is a dominant process in the early stage of the two-proton emission. When the diproton correlation is absent, the sequential two-proton emission competes with the diproton emission, and the decay width is underestimated. These results suggest that the two-proton emission decays provide a good opportunity to probe the diproton correlation in proton-rich nuclei beyond the proton drip-line.

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Tomohiro Oishi, Kouichi Hagino, Hiroyuki Sagawa. 2014-04-11. Role of diproton correlation in two-proton emission decay of the $^6$Be nucleus. https://doi.org/10.1103/physrevc.90.034303

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