Observation of the near-threshold intruder $0^{-}$ resonance in ${}^{12}$Be

Abstract

A resonant state at $3.21_{-0.04}^{+0.12}$\,MeV, located just above the one-neutron separation threshold, was observed for the first time in ${}^{12}$Be from the ${}^{11}$Be\,$(d,p{)}^{12}$Be one-neutron transfer reaction in inverse kinematics. This state is assigned a spin-parity of $0^{-}$, according to the distorted-wave Born approximation (DWBA) and decay-width analysis. Gamow coupled-channel (GCC) and Gamow shell-model (GSM) calculations show the importance of the continuum-coupling, which dramatically influences the excitation energy and ordering of low-lying states. Various exotic structures associated with cross-shell intruding configurations in ${}^{12}$Be and in its isotonic nucleus ${}^{11}$Li are comparably discussed.

References in corpus (12)

• Shell Model in the Complex Energy Plane
• Shell Structure of Exotic Nuclei
• Shell-model study of boron, carbon, nitrogen and oxygen isotopes based on monopole-based-universal interaction
• Measurement of two-halo neutron transfer reaction p(${}^{11}$Li,${}^9$Li)t at 3$A$ MeV
• Coexistence of BCS and BEC-like pair structures in halo nuclei
• Positive-parity linear-chain molecular band in ${}^{16}$C
• Efimov states and their Fano resonances in a neutron-rich nucleus
• Convenient location of a near-threshold proton-emitting resonance in ${}^{11}$B
• Three-body structure of low-lying 12Be states
• Structures and decay properties of extremely proton-rich nuclei ${}^{11,12}$O
• Ordering of the $0d_{5/2}$ and $1s_{1/2}$ proton levels in light nuclei
• Determination of the cluster-decay branching ratio from a near-threshold molecular state in ${}^{10}$Be

Cited by in corpus (2)

• Recent progress in configuration-interaction shell model
• Calculation of the Thomas-Ehrman shift in ${}^{16}$F and ${}^{15}$O(p,p) cross section with the Gamow shell model