${}^{22}$C: $S$-Wave Two-Neutron Halo

Abstract

A dripline nucleus ${}^{22}$C is studied in a Borromean three-body model of ${}^{20}$C+$n$+$n$. The valence neutrons, interacting via a realistic potential, are constrained to be orthogonal to the occupied orbits in ${}^{20}$C. We obtain ample results supporting that ${}^{22}$C is an ideal $S$-wave two-neutron halo nucleus: The ground state is bound by 390-570 keV, the root mean square neutron and proton radii are 4.0 and 2.4 fm, and the two neutrons are predominantly in $(s_{1/2}{)}^2$ orbits. The binding mechanism of ${}^{22}$C is discussed. One- and two-body density distributions elucidate the halo character as well as the correlated motion of the neutrons. The reaction cross sections of ${}^{22}$C+${}^{12}$C collisions are predicted.

8 pages, 4 figures

Cited by in corpus (2)

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