The Borromean nucleus 17Ne (15O+ p+ p) is investigated by using the hyperspheric
adiabatic expansion for a three-body system. The measured size of 15O and the low-lying
resonances of 16F (15O+ p) are first used as constraints to determine both central and spin-
dependent two-body interactions. Then, the ground state structure of 17Ne is found to be an
almost equal mixture of s2 and d2 proton-15O relative states, the two lowest excited states
have about 80% of sd-mixed components, and for the next two excited three-body states the …