Visualizing N-11 by resonance reactions

The proton-rich, unbound nucleus N-11 has been studied using the technique of elastic resonance scattering in inverse geometry. The spins and parities of the three lowest resonance levels have been determined as 1/2(+), 1/2(-) and 5/2(+), resulting from the orbitals 1s(1/2), 0p(1/2) and 0d(5/2), respectively. This level ordering is the same as the one found in the mirror nucleus of N-11, namely the one-neutron halo nucleus Be-11. Especially, the in Be-11 well known level inversion, where the ground state is a 1/2(+) intruder state below the from a naive shell model expected ground state 1/2-, is also found in N-11.