Cluster structure of 8p-4h states in Ne20

The structure of high-lying states in Ne20 has been studied using the C12(C12, ±)Ne20 reaction at E(C12)=64 and 80 MeV. The spins and branching ratios to the ± +O16 channel were determined by measuring double (±-±) and triple (±-±-) angular correlations. The branching ratios for decay to the C12 + Be8 channel were obtained from an ±-C12 coincidence experiment. In addition to confirming the spins of several lower-lying states, we have made a spin assignment of 8+ for the state at 18.538 MeV and also suggest assignments to states at 17.259 MeV (7-), 20.478 MeV (8+), and 24.378 MeV (7-). The 13.927-MeV (6+) state is assigned to the K=02+ band, and it is suggested that this band also includes the 8+ state at 20.478 MeV. The 18.538-MeV (8+) state was found to have a large reduced width for decay into C12 + Be8 which, together with its small reduced width for decay to ± +Og.s.16,suggests that it has a large C12 + Be8 cluster parentage. This state appears to be the 8+ member of a new 8p-4h band which has the 12.436-MeV (06+) state as its band head and the state at 15.159 MeV as its 6+ member. The discovery of such a rotational band in Ne20 with a large C12 + Be8 cluster parentage and a large moment of inertia provides the first direct indication of correlations between the clusters in 8p-4h states. NUCLEAR STRUCTURE Ne20; measured spins, parities, branches to +O16 and C12 + Be8; deduced reduced widths, cluster structure.