Few-body structures in the mirror nuclei O-11 and Li-11

摘要

We investigate the dripline mirror nuclei Li-11 and O-11, located on the neutron and proton dripline, respectively. We calculate the lowest four states, 3/2(-), 1/2(+), 3/2(+), and 5/2(+), built on double occupancy in the nuclear s(1/2 )and p(1/2) valence single-particle states. We use the hyperspherical adiabatic expansion method to solve the three-body problem for a frozen nuclear core surrounded by two identical nucleons. The four analog states in O-11 are obtained with precisely the same interactions as used for the four states in Li-11, except for addition of the Coulomb interaction from the charge of the substituted valence protons. Surprisingly, the four energies deviate from each other only by less than a few hundred keV. Any of them could then turn out to be the ground state, due to the uncertainty related to the angular momentum and parity dependence of the three-body potential. Still, our calculations marginally favor the 1/2(+) state. The structures of these four states in O-1(1) deviate substantially from the analog states in the mirror, Li-11.