Structure of T Ä 2 24 Ne from 14 C on 14 C

The C(C,a) reaction at 22 MeV was used to study T52 Ne. Charged particles were detected with a Si detector telescope at 0°, and g transitions in coincidence were detected with an array of three Comptonsuppressed ‘‘clover’’ detectors and seven Compton-suppressed single Ge crystals. The a-g and a-g-g coincidence data were analyzed to study the structure of Ne. Twenty-two new g lines were assigned to 14 new levels. Angular distribution measurements provided spin assignments and restrictions to a number of levels. Likely candidates were found for the lowest 5 and 6 levels. All but one of the 12 states predicted to lie below 6 MeV by shell model calculations using the universal s-d interaction were observed. The rms deviation in excitation energies among these is 190 keV, and there is a tendency for the observed levels to lie somewhat higher than the predicted ones. A comparison of the structure of Ne with its neighbors suggests a significant shell gap above the nd5/2 orbital in agreement with the large d5/2-s1/2 gap implied by the effective singleparticle energies in the universal s-d shell model interaction.