Measurement of Unbound Excited States of 24O

The unbound excited states of the most neutron-rich oxygen isotope, O-24 (Z = 8, N = 16), have been investigated using the O-24(p,p')O-24*-->O-23+n reaction at RIKEN, where a 63 MeV/neuclon secondary beam of O-24 was produced in a Be production target by the projectile-like fragmentation of a 95 MeV/u Ar-40 primary beam. The first 2(+) excited state was observed in the invariant mass spectrum. This experiment; will give us a deeper understanding of the new magic number at N = 16 in the neutron-rich oxygen isotopes.