Complete set of bound negative-parity states in the neutron-rich 18N nucleus

Abstract

High-resolution gamma-ray spectroscopy of 18N is performed with the Advanced GAmma Tracking Array AGATA, following deep-inelastic processes induced by an 18O beam on a 181Ta target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in 18N below the neutron threshold. Spin and parities are proposed for all located states on the basis of decay branchings and comparison with large-scale shell-model calculations performed in the p-sd space, with the YSOX interaction. Of particular interest is the location of the 0^-_1 and 1^-_2 excitations, which provide strong constrains for cross-shell p-sd matrix elements based on realistic interactions, and help to simultaneously reproduce the ground and first-excited states in 16N and 18N, for the first time. Understanding the 18N structure may also have significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.

References in corpus (6)

• Shell-model study of boron, carbon, nitrogen and oxygen isotopes based on monopole-based-universal interaction
• Current Status and Future Potential of Nuclide Discoveries
• Formation of light exotic nuclei in low-energy multinucleon transfer reactions
• The nuclear force imprints revealed on the elastic scattering of protons with ${}^{10}$C
• Accessing tens-to-hundreds femtoseconds nuclear state lifetimes with low-energy binary heavy-ion reactions
• Experimental nuclear astrophysics in Italy

Cited by in corpus (4)

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• Gamow shell model study of the 17Ne(p, p) reaction and of isospin symmetry breaking in 18Na
• Study of the Isomeric State in ${}^{16}$N Using the ${}^{16}$N${}^{g,m}$($d$,${}^3$He) Reaction