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arXiv · 1101.0988

Constraints on two-neutron separation energy in the Borromean $^{22}$C nucleus

M. T. Yamashita·R. S. Marques de Carvalho·T. Frederico·L. Tomio
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Abstract

The recently extracted matter radius of carbon isotope $^{22}$C allows us to estimate the mean-square distance of a halo neutron with respect to the center-of-mass of this nucleus. By considering this information, we suggest an energy region for an experimental investigation of the unbound $^{21}$C virtual state. Our analysis, in a renormalized zero-ranged three-body model, also indicates that the two-neutron separation energy in $^{22}$C is expected to be found below $\sim$0.4~MeV, where the $^{22}$C is approximated by a Borromean configuration with a pointlike $^{20}$C and two $s$-wave halo neutrons. A virtual-state energy of $^{21}$C close to zero, would make the $^{22}$C, within Borromean nuclei configurations, the most promising candidate to present an excited bound Efimov state or a continuum three-body resonance.

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M. T. Yamashita, R. S. Marques de Carvalho, T. Frederico, L. Tomio. 2011-01-05. Constraints on two-neutron separation energy in the Borromean $^{22}$C nucleus. https://doi.org/10.1016/j.physletb.2011.01.040

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