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Parity inversion, breakdown of shell closure and particle-vibration coupling in Be-isotopes

G. Gori·F. Barranco·E. Vigezzi·R. A. Broglia
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Abstract

The coupling of single-particle motion and of vibrations in $^{11}_4$Be produces dressed neutrons which spend only a fraction of the time in pure single-particle states, and which weighting differently from the bare neutrons, lead to parity inversion. The interaction of the two least bound neutrons in the ground state of $^{12}_4$Be mediated by the $v_{14}$ Argonne nucleon-nucleon potential and by the exchange of the phonon cloud, give rise to a strongly correlated state, where the neutrons spend more than half of the time in (s$^2$+d$^2$)-configurations, resulting in a breaking of the N=8 shell closure.

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G. Gori, F. Barranco, E. Vigezzi, R. A. Broglia. 2003-01-30. Parity inversion, breakdown of shell closure and particle-vibration coupling in Be-isotopes. https://arxiv.org/abs/nucl-th/0301097

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