Structure of T=2 ²⁴Ne from ¹⁴C on ¹⁴C

The ¹⁴C(¹⁴C,α) reaction at 22 MeV was used to study T=2 ²⁴Ne. Charged particles were detected with a Si detector telescope at 0°, and γ transitions in coincidence were detected with an array of three Compton-suppressed “clover” detectors and seven Compton-suppressed single Ge crystals. The α-γ and α-γ-γ coincidence data were analyzed to study the structure of ²⁴Ne. Twenty-two new γ 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 ²⁴Ne with its neighbors suggests a significant shell gap above the νd_5/2 orbital in agreement with the large d_5/2-s_1/2 gap implied by the effective single-particle energies in the universal s-d shell model interaction.