Complete set of bound negative-parity states in the neutron-rich nucleus N18

High-resolution γ-ray spectroscopy of N is performed with the Advanced GAmma Tracking Array AGATA, following deep-inelastic processes induced by an O beam on a Ta target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in N 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 01 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 N and N, for the first time. Understanding the N structure has significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.