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arXiv · 2008.01420

Continuum and three-nucleon force in Borromean system: The 17Ne case

Y. Z. Ma·F. R. Xu·N. Michel·S. Zhang·J. G. Li·B. S. Hu·L. Coraggio·N. Itaco·A. Gargano
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Abstract

Starting from chiral two-nucleon (2NF) and chiral three-nucleon (3NF) potentials, we present a detailed study of 17Ne, a Borromean system, with the Gamow shell model which can capture continuum effects. More precisely, we take advantage of the normal-ordering approach to include the 3NF and the Berggren representation to treat bound, resonant and continuum states on equal footing in a complex-momentum plane. In our framework, 3NF is essential to reproduce the Borromean structure of 17Ne, while the continuum is more crucial for the halo property of the nucleus. The two-proton halo structure is demonstrated by calculating the valence proton density and correlation density. The astrophysically interesting $3/2^-$ excited state has its energy above the threshold of the proton emission, and therefore the two-proton decay should be expected from the state.

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Y. Z. Ma, F. R. Xu, N. Michel, S. Zhang, J. G. Li, B. S. Hu, L. Coraggio, N. Itaco, A. Gargano. 2020-08-05. Continuum and three-nucleon force in Borromean system: The 17Ne case. https://doi.org/10.1016/j.physletb.2020.135673

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